None
^-Diazo-di-nitro-toluene o-sulphonic acid C0HMe(NO.,)2 From _p-toluidine o- sulphonic acid and fuming HNOS (Pagel, A, 176, 306). Yellowish needles. Not affected by alcohol boiling under 1,000 mm. pressure. Diazo-oxy-acrylic ether (?) C,H6N,03 i.e. CN2:C(OH).CO.JEt (?). (142°) at 717 mm. V.D. = 5'0 (obs.). Yellow oil of strong peculiar odour. Volatile with steam. Formation. — Gelatine, swollen with water, iu warmed with absolute alcohol whilst HC1 gas is passed in, it soon dissolves and after dis- tilling off the alcohol a thick brown syrup is left ; the latter, which appears to be the hydrochloride of amido-oxy-acrylic ether CH(NH2):C(OH).CO2Et yields the diazo-ether when its concentrated aqueous solution is treated with NaN02 ; it is purified by distillation with steam ; the yield is 150 grms. from 400 grins. of gelatine. Reactions. — Acids eliminate its nitrogen, but it is very stable towards alkalis, with the ex- ception of NH3, which even in the cold soon splits off C02 and alcohol. By zinc-dust and acetic acid it is reduced first to a hydrazine and finally to an amido-acid. An ethereal solution of iodine converts it into di-iodo-oxy-acrylic ether CI.j:C(OH).C02Et which on treatment with cold aqueous NH3 loses CO2 and alcohol and yields di-iodo-vinyl-amine CI2:CH(NH2). It reduces AgNO3 in the cold (Buchner a. Curtius, B. 19, 850). Diazo-o-oxy-benzoic acid C.H^CO^X^ [CO.,H:0:N = 1:6:8]. Diazo-salicylic acid. Formed by passing N203 into an aqueous or alcoholic solution of hydro- chloride of amido-salicylic acid and concentrating. Crystallised from water (Schmitt, J. 1864, 384 ; Goldberg, J. pr. [2] 19, 362 ; P. F. Frankland, C. J. 37, 749). Slender needles. Reactions. — 1. Boiled with cone. HI it gives iodo-salicylic acid [196°] (q. v.). — 2. Mercaptan at 170° gives salicylic acid (Schmitt a. Mitten- zwey.J.pr. [2] 18, 193). Chloride. — C,^aa(C02H)(OH)N2Cl. — Pla- tino-chloride{C6H3(C02H)(OH)N2Cl}?PtCl4. Diazo-//-oxy-benzoic-amido-oxy-benzoic acid. Dimethyl derivative. Diazo-amido-anisic acid CaH3(OMe)(CO2H).N2.NH.C6H3(OMe)(C02H). Formed by passing nitrous acid gas into a cold alcoholic solution of amido-anisic acid (Griess, A. 113, 337 ; 117, 45). Amorphous powder, insol. water, alcohol, and ether. Warm cone. HC1 converts it into a red acid C,gHI407. — Na A"l£aq. — K A"2aq. — Et^A" : narrow leaflets. Diazo-oxy-cinnamic acid. Methyl deriva- tive CBH,,(N.,OH)(OMe).CH:CH.C02H [5:2:1]. Formed by diazotising methoxy-amido-cinnamio acid. The chloride forms yellow crystals, which decompose at about 102°. The nitrate C6H3(N:N.NOJ)(OMe)(C.iH2.COiH) crystallises in yellow needles, which explode at 152°, nearly insoluble in cold water, alcohol, and ether (Schnell, B. 17, 1385). o-diazo-phenol. Chloride CBH4(OH)N2CL By passing N.^O,, into an alcoholic solution of the hydrochloride of o-amido-phenol, and then adding ether (Schmitt, B. 1, 67 ; Bohmer, J. pr. 132, 460). Bhombohedra. Bromine-water added to its equeous solution forms a yellow pp. of diazo-dibromo-phenol (q. v.). Sulphite C.H4(OH).N2.S03Kaq. Golden scales, got by adding KHSO, to C?H4(OH) N2C1 (Schmitz a. Glutz, B. 2, 51 ; Reisenegger, A. 221,314). Platinochloride (C8H4(OH)N2Cl)2PtCl4. m-Diazo-phenol. Ethyl derivative (Wag- ner, J. pr. [2J 32, 70). 2>-Diazo-phenol. Nitrate C6H4(OH).N2NCv Formed by passing nitrous acid gas into a cold ethereal solution of phenol (Weselsky, Site. B. 1875, 9; .B. 8, 895), or of ^-nitroso-phenol (Jager, B. 8, 894). Preparation. — By passing N203 into alcoholic solution of hydrochloride of p-amido-phenol, adding strong HN03 and cooling strongly (Boh- mer, J. pr. 132, 450). Reactions. — 1. By warming with dilute HBr (15 per cent, solution) it does not give off nitrogen, as diazo-benzene nitrate would do, but forms di-azo-di-bromo-benzene in accordance with the equation : 8C.H,Br,<$ + 3C.H.< NaBr + 3NO, + 3NO + 9H.O. Chloride C6H4(OH).N,,C). Formed by diazotising jp-amido- phenol hydrochloride, Converted into hydroquinone by boiling cone. HC1 or dilute H2SO4 (Schuler, B. 9, 1160). Heated with mercaptan it gives phenol and (C.H5)2S2 (Schmitt a. Mittenzwey, J. pr. [2] 18, 194).— (C6H4(OH).N2Cl)2PtCl4. Bromide CBH4(OH)N.JJr. Formed by pass- ing N203 into an alcoholic solution of the hydro- bromide of jp-amido-phenol (C. Bohmer, J. pr. 132, 451). Precipitated by ether. Platinobromide (CdH4(OH)N.iBr),PtBr1. Needles grouped in spherical segments. Got by adding an aqueous solution of PtBr4 (prepared like PtCl4 by dissolving spongy platinum in HBr mixed with HNOS and evaporating) to one of diazo-phenol hydrobromide. If left for sever.il days in contact with their mother liquor, t.ie crystals absorb eight molecules of water of crystallisation changing to blood-red twin crystals resembling gypsum. These are in- soluble in ether, CS2 and CHC1,, difficultly soluble in water. The salt heated with 10 pts. oi Na-^COj does not yield bromophenol. Sulphate C6H4(OH)N2.S04H. Obtained by adding dilute H2S04 to an alcoholic solution of the hydrochloride of p-amido-phenol, passing in N...O., and adding ether. Needles. Does nut explode when heated. Converted by boiling HBr into the bromo-phenyl ether of hydro- quinone (q. v.). Sulphite HO.C6H4.N,.SOjK. Fromp-amido- phenol, HC1, NaN02, and K,SO, (Keisenegger, A. 221, 316). Yellowish plates. Ethyl derivative xC0H,(OEt)N2OH Salts.— CBH4(OEt)N.jCl. From p-amido-phenetol hydro- chloride by solution in alcohol and treatment with N.,0,. Precipitated by ether as an oil. 414 . DIAZO- COMPOUNDS. Crystallises when cooled to - 18°. But if H2S04 be added to the alcoholic solution of the chloride, avoiding rise of temperature, crystals of the sulphate C6H4(OEt)N2.S04H separate. Boiled with water this forms C6H4(OEt)(OH), hydro- quinone mono-ethylic ether (q. v.) (Hantzsch, J.pr. 130,461). Methyl derivative. The salts are formed by diazotising ^j-anisidine (Salkowski, B. 7, 1009) : C6H4(OMe).N2NOs.- C6H4(OMe).N2.S04H. Diazo-phenol-carbamic ether. Ethyl deri- vative C6Hs(OEt .N )< \N ^- \ Preparation. — By passing N20S into a solu- tion of the hydrochloride of ethoxy-amido- phenyl-urethane, C6H3(OEt) (NHJ.NH.CO^t, HC1 (Kohler, J.pr. [2] 29,273). Properties. — Slender, silvery- white matted needles. Insol. water, sol. alcohol, ether, and glacial acetic acid. Decomposes below 100°. Reactions. — 1. Does not explode. — 2. Not affected by boiling alcohol. — 3. Boiled with soda, it is decomposed with evolution of nitrogen. Diazo-plienol sulplumc acids CBHS(N2OH)(OH)(SO3H) [1:4:3] and [3:4:1] are unstable crystalline acids obtained by diazo- tising the corresponding amido-phenol sulphonic acids (Beunewitz, J". pr. [2] 8, 52). Diazo-phenol disulphonic acid N2 C6H2(S03H).£ | . From p-amido-phenol di- \O eulphonic acid (q. v.) (Wilsing, A. 215, 238). Salt. — K2A"aq. Small sulphur - yellow needles. Warmed with water it forms hydro- quinone disulphonic acid. 2>-p-Tetra-azo-diphenyl Nitrate N03.N2.C5H4.C6H4.N2NOS. Formed by passing nitrous acid gas into an alcoholic solution of nitrate of benzidine, and ppg. with ether (Griess, Tr. 1864, iii. 719). White needles, v. sol. water, m. sol. alcohol, insol. ether. Explodes when heated. Boiling water forms y^p-di-oxy-diphenyl. Perbromide Br3N2.C6H4.C8H4.N2Brs. JmideNs.C6H4.C6H4.Nr [127 ']. White plates. Platinochloride (ClN2.C6H1.CljH4.N2Cl)PtCl4: yellow plates. Sulphate (HS04N2.CsH4.C4H4.N2S04H)H.iS04 : white needles. Anilide PhNH.N2.C6H4.C6H4.N2.NHPh : lance-shaped crystals, insol. water. Explosive. Piperidide C,H10N.N2.C6H,.C<jH4.N2.NC5H)0. From benzi- dine by diazotisation and treatment with piperi- dine. Insol. water, si. sol. alcohol, v. sol. ether (Wallach, A. 235, 271). ra-wi-Tetra-azo-diphenyl (Brunner a. Witt, B. 20, 1028). Diazo-phenyl-carbamic ether /N2\ C.H/ y ^N— COjEt. Formed by diazotising o- *mido-phenyl-carbamic ether (Rudolph, B. 12, 1296). Hexa-azo-ti i-pheny 1-carbinol Chloride {CiH^Cl^COH. Diazo-p- rosaniline chloride. Formed by diazotising p- rosaniline hydrochloride (E. a. 0. Fischer, A. 194, 274).— C19H13N6Cl33AuCl3. Hexa-azo-tri-phenyl-carbinyl cyanide Chloride {CdH4(N2Cl)|3C.CN 2aq. From hydrocyano-2>-rosaniline hydrochloride by diazo- tisation. Slender needles, v. sol. water. Gives, with boiling water, (C6H4OH)3C.CN (Fischer, A. 194, 275). Hexa-azo-tri-phenyl-methane chloride (C6H4N2C1)3CH. Diazo-p-leucaniline. Formed by diazotising tri-amido-tri-phenyl-methane- hydrochloride (E. a. O. Fischer, A. 194, 269). Gives jj-rosolic acid (aurin) when boiled with water. Di-azo-phenyl methyl ketone sulphite of sodium CH3.CO.CIJH,.N.,.S03K. Formed by di- azotising o-amido-acetophenone and treating the product with K2S03. On reduction it gives the hydrazine salt: CH3.CO.CdH4.NH.NHS03K whence HC1 forms methyl-indazol, /CMe C6H4< l\ (v. INDAZOL). The aqueous solu- \N-NH tion of the hydrazine salt changes to /CMe C6H4<( |\ ^•N — N.S03Na methyl-indazol sulphonate of sodium (Fischer a. Tafel, A. 227, 305). Hexa-azo-di-phenyl-tolyl-carbinol. Chloride (C,H4N2Cl)2C(OH).C6H3MeN.,Cl. Diazo-rosaniline. Formed by diazotising rosani- line hydrochloride (Caro a. Wanklyn, Z. 1866, 511; E. a. 0. Fischer, A. 194, 279). Gives rise to rosolic acid when boiled with water. — (C^H, 5N6Cls)23PtCl4 6aq.— C^H^NgClgSAuCls. Hexa-azo-di-plienyl-tolyl - carbinyl cyanide. Chloride (C6H4N2Cl)2:C(CN).C6H3MeN2Cl. Diazohydrocyan - rosaniline. — Gold salt. — C20H14(CN)N6Cl33AuCl3. Diazo-resorcin chloride. Diethyl ether C6H3(OEt)2N2Cl. From the amido- compound (Pukall, B. 20, 1136). Unstable crystals. Diazo-rosaniline (v. supra). Diazo-salicylic acid v. DIAZO-OXY-BEXZOIO AGED. Diazo-succinamic acid C02H.CH2.CN2.CONH2. Methyl ether A'Me: [84°]; long yellow prisms (from alcohol). Formed by the action of aqueous NHS upon methyl diazo-succinate. By decomposition with cold slightly acidified water it yields methyl fumaramate and methyl malamate. Heated with benzoic acid at 140°- 150° it gives methyl benzoyl-malamate. Iodine in ethereal solution converts it into methyl di - iodo- succinamate— CO.jMe.CH.j.CI2.CONH., (Curtius a. Koch, B. 19, 2460). Ethyl ether C,^N,(CONH2)(C02Et — [112°] ; long thin yellow prisms ; easily soluble in hot water and alcohol, sparingly in cold water and ether. It is not altered by boiling with pure water, but by acids and alkalis is at once decomposed with evolution of nitrogen. Reduced to aspartic ether by zinc-dust and acetic acid (Curtius a. Koch, B. 18, 1293). Diazo-succinic acid C-jH-jN^CO-jH).,. The di-methyl and di-ethyl ethers of this acid are obtained by mixing iced solutions of the hydrochlorides of the aspartic ethers CO,R.CH(NH3C1).CH.,.COJI and sodium nitrite, arid adding a few drops of dilute H2S04, after DIAZO- COMPOUNDS. 415 which the product is shaken out with ether. The ethers form dark-yellow oils which have not yet been obtained in a pure state. By boil- ing with water or aqueous acids they are decom- posed with evolution of nitrogen and formation of the corresponding fumario ether. They decompose spontaneously on keeping, evolving nitrogen and forming azinsuccinic ethers (CO.jBJ.jC.jH.jiN.NrC.jH^CO.jBJ.j. Strong aqueous NH3 converts them into diazo-succinamic ethers. ^-Diazo-toluene. Salts. — The preparation and properties of these salts resemble those of the corresponding diazo-benzene salts (Griess, C. J. 20, 86). — C<jH1Me.N2.NO, : long slender white needles. — (CdH4Me.N.,Cl)2PtCl4 : yellow prismatic crystals. C6H4Me.N2S04H.- C.H.Me.NrBr,. Dicyanide C9H,,N4 or C8H;Me.N2.CN,HCN. [78°]. Needles or leaflets. Formed by the action of a diazo-toluene salt on a solution of KGN (B. 12, 1638). Anilide CdH4Me.N2.NHPh or, alternatively, Ph.N.j.NH.CaH.Me. From ^-toluidine and di- azobenzene nitrate or from aniline and p-diazo- toluene nitrate (Griess, A. 137, 60 ; B. 7, 1619). Narrow yellow leaflets. By warming with phenol it gives a mixture of aniline.p-toluidine, benzene- azo-phenol and 2>-toluene-azo-phenol ; similarly •with resorcin (Heumann a. Oeconomides, B. 20, 907). p-Chloro-anilide. Formed from p- chloro-diazo-benzene and jp-toluidine. By heat- ing with phenol it gives p-toluene-azo-phenol and p-chloraniline (Heumann a. Oeconomides, B. 20, 909). Piperidide C12H17N., i.e. C,H;.N2.NC.H10 [41°]. From CHS.C,,H4.N.C1 and piperidine. Prisms (from alcohol or ether). Insol. water. Dry HC1 passed into its solution in petroleum- ether appears to form an unstable hydrochloride, quickly decomposing into diazotoluene chloride and piperidine hydrochloride (Wallach, A. 235, 214). p-Toluide C«H4Me.N2.NH.C6H4Me. [116°]. Formed by passing nitrous acid gas into a solu- tion of p-toluidine in alcohol and ether (Griess, A. 121, 277 ; when pure (by digestion with alcoholic (NH,)2S) it forms nearly colourless large thin prisms (Bernthsen a. Goske, B. 20, 928). p-Ethyl-toluide C6H1Me.N2.NEt.CsH4Me. Decomposed by acids into tthyl-p-toluidine and p-diazo-toluene chloride (Gastiger, Bl. [2] 42, 342). o-Diazo-toluene-o-toluide [2:1] C6H4Me.N2.NH.CrH4Me [1:2]. [51°]. Orange-yellow powder of microscopic needles. Prepared by adding sodium nitrite (1 mol.) to an aqueous solution of o-toluidine (2 mols.) and HC1 (3 mols.) and then neutralising the HC1 with sodium acetate, the temperature being kept below - 5° during the whole reaction. It is crystallised by dissolving in cold alcohol and adding ice (Fischer a. Wimmer, B. 20, 1582). o-Diazo-toluene-azo-teluene C14HUN4.OH i.e. ,N— N.OH C,H,£ || . (?) Obtained by diazotising \N— N.C7H7 toluene-azo-o-toluidine ; the salts crystallise out when a stream of nitrous acid gas is passed into an alcoholic solution of toluene-o-azo- toluidine and an excess of acid, or upon subsequent addition of a little ether. On heating with water or alcohol it decomposes, evolving nitrogen like ordinary diazo-compounds. By SnCLj or S02 it is not reduced to a hydrazine but gives a stable compound CMHI4N4 which .N— NH probably has the constitution C,HS< I I , \N-NC7H7 by bromine this body is reconverted into the diazo-perbromide. By.zinc-dust and alcohol it is converted into ra-toluene-^-azo-toluene [68°] with evolution of nitrogen. The diazo-imide loses nitrogen on heating and yields tolyl- azimido toluene C7Hd^ | \N.C7H; identical with that obtained by oxidation of toluene-azo-o-tolui- dine. o-Diazo-toluene-azo-toluene reacts with amines and phenols like an ordinary diazo- compound ; the products, however, reduce to a diamine or amido-phenol and tolyl-azimido- toluene. All the salts have a deep orange-yellow colour and are tolerably stable. — CI4H1SN4.C1X : red granular crystals. — (CuHlsN4.Cl)2PtCl4 : yel- low acicular crystals. — C, ,H|.,N4.NOSX : slender red pointed crystals.— C^n^N^SO^* : red in- terwoven needles.— C,4H13N4.Br,: [125°], long glistening red needles or compact crystals. Imide C14H,.,NS: [85'], thick yellowish red crystals ; formed by the action of alcoholic NH, upon the perbromide (Zincke a. Lawson, B. 19, 1452). Product of Reduction C,4HHN4 probably ,N— NH C;HX I I [168°]. Long colourless \N— N.C.H7 needles. V. sol. hot alcohol, si. sol. ether and chloroform, insol. water. It has no basic properties. It is not affected by reducing agents. Bromine in alcoholic or acetic acid solution readily converts it into o-diazo- toluene-azo-toluene perbromide. On addition of Ag.jO to its alcoholic solution nitrogen is evolved and w-p-azotoluene [58°] is formed. Acetyl derivative C14HlsN4Ac [134°]: glistening white plates (Zincke a. Lawson, B. 19, 1457). _p-Diazo-toluene-azo-toluene [2:1] C6H4(CH3)— N2— CdH3(CH3).N2OH [1:3:4]. Prepared by dissolving toluene-azo-p-toluidine in alcohol, adding an excess of HC1, diazotising by passing N.,0, into the well-cooled solution, and precipitating the diazo-salt with ether. By reduction with SnCL or zinc-dust and acetic acid in cold dilute aqueous solution it is split up (without formation of a hydrazine) inta o-toluidine and tolylene-p-diamine. Salts.— XC14H13N4.N03: slender brownish- yellow needles, m. sol. water and alcohol. — CnH,.,N4.Br, : yellow crystalline pp. which changes on standing to small violet needles. — C, ,Hl3N,.SO,Na : glistening scales (from alcohol), v. sol. hot. alcohol, si. sol. water. Imide C,,HI3NS: [CO0]; long plates; sol. alcohol and acetic acid (Zincke a. Lawson, B. 20, 1181). o-Diazo-tolucne m-sulphonic acid »MeCsHs<g0N> [l f]. Precipitated as a white powder when nitrous gas is pasced into a 416 DIAZO- COMPOUNDS. cold solution of o-toluidine sulphonic acid. Explodes feebly at 100° (Nevile a. Winther, C. J. 37, 628). o-Diazo-toluene p-sulphonic acid. Minute monoclinio prisms (Hayduck, A. 172, 213; 174, 344). Boiling alcohol produces Me.CBH3(OEt).S03H [1:2:4]. ;i-Diazo-toluene o-sulphonic acid. Yellow or brown needles (Ascher, A. 161, 8 ; Jensen, A. 172, 235). Heated with alcohol under pressure it gives MeCBH,(OEt)(S03H) Remsen a. Palmer, Am. 8, 243). /i-Diazo-toluene m-sulphonic acid *MeC,H3<g^> [ij]. More soluble than the corresponding o-compound (Nevile a. Win- ther, C. J. 37, 631). Prepared by passing nitrous acid gas into jj-toluidine sulphonic acid suspended in alcohol. Hot alcohol gives toluene w-sulphonic acid (Petermann, A. 173, 201). p-Diazo-toluene exo-sulphonic acid CBH4<^JJ?>>SOS. Heated with alcohol under 1,100 mm. pressure it gives CBH1(OEt).CH..SO3H (Mohr, A. 221, 219). p - Diazo - toluene - snlphonic - amido - toluene sulphonic acid. Amide [1:4:2] C.HsMe<S02NHa)N,NH.C.H,Me.SO,'NH.1 [2:1:4]. Prom C8H3Me(NH2)S02NH2 [1:2:4], alcohol, and nitrous acid gas (Paysan, A. 221, 211). Decom- posed by HC1 into N2, C6H3ClMe.S02NH2, and C6H3(NH2) Me.SO2NH?. o-Diazo-toluene disulplionic acid .N., From and CBH2Me(S03H)< | " fl*:!!. \SOS L aqueous o-toluidine disulphonic acid at 0° (Lim- pricht, B. 18, 2176 ; Hasse, A. 230, 291). Micro- scopic needles. Explosive. Heated with alcohol under pressure it gives CtiH2Me(OEt)(S03H)2. With HI it forms C,,H2MeI(SOsH)2. Salt B.— K A'.— BaA'2 4aq.— Pb A'2. 2>-Diazo-toluene di-sulplionic acid QJBMtfBQJXK I * . Formed by diazotisation \SOS 'of p-toluidine- di- sulphonic acid. Yellowish crystals. By heating with HI it yields p-iodo- toluene-di-sulphonic acid; with HBr it yields p-bromo-toluene-di-sulphonic acid. Salts. — A'K: large yellow prisms. — A'2Ba : yellowish white needles. — A'2Pb : small red prisms (Limpricht, B. 18, 2178). Diazo-toluic-amido-toluic acid C6H.,Me(Cq,H).N,.NH.C6H3Me.CO2H. From amido-toluic acid and nitrous ether (Griess, A. 117, 59). Minute yellow prisms (containing ij aq) ; insol. water, alcohol, and ether. o-Diazo-p-toluidine bromide. Acetyl derivative C«H:,Me(NHAc).N2Br [1:4:2]. From CBH,Me(NHAc)(NH2) [1:4:2], cone. HBr and cone. NaNO2 at O3 (Wallach, A. 235, 249). Reactions. — 1. Hot Ac2O converts it into CsHsMe(NHAc)(OAc) [132-5°].— 2. Nitro-ethane and NaOEt give CgHsMe(NHAc).N2.CHMe(NO2). [143°].— 3. HNEt2 gives C6H3Me(NHAc)N2.NEt2. [108°]. — 4. Pipendine gives the piperidide: CBH3Me(NHAc).N2.NC,H11). [154°]. HC1 passed into an alcoholic solution of this base gives a pp. of C HsMe(NHAc)N2Cl. Boiling HClAq gives C(jH3Me(NHAc)Cl. Diazo -w-xylene- sulphonic acid C6H.,Me2<^ y. [1:3:4:6]. White pp. Sparingly soluble in water. Decomposes at 60°-70°. Combines with phenols and amines. Formed by diazotisation of m-xylidine-su!phonic acid (Nolting a. Kohn, B. 19, 138). Diazo-p-xylene-sulphonic acid CBH2Me2<^ ^> [la jj] . Yellowish white plates. Stable at ordinary temperature, decomposes on heating with water at 60°-70°. Formed by the diazotisation of p-xylidine-sulphonic acid CliR!Me2(NH.i)(SOsH) [1:4:2:5] (Nolting a. Kohn, B. 19, 141). DISAZO- COMPOUNDS. Secondary azo- com- pounds. Compounds containing two azo- groups of the form C — N2 — C. The general methods by which they may be prepared are given in the article on azo- colouring matters (p. 368). The nomenclature here used is like that used for azo- compounds. To find the name of a disazo- compound, write down the formula, strike out everything between the two N2 groups, remove one of the N2 groups, and join the remaining parts of the formula together and name the resulting azo- compound as directed on p. 369. Then insert after the word ' azo ' the name of the central hydrocarbon, preceded by prefixes representing its substituents and followed by ' azo.' Di - amido - benzene - azo-benzene-azo-benzene sulphonic ac'd [4:l]C6H,(S03H)-N2-CdH4-N2-CBH,(NH,)2 I [1:2:4]. Formed by the combination of diazo- i benzene-azo-benzene-p-sulphonic acid with m- phenylene diamine. Bed microscopic needles. V. si. sol. alcohol and ether. In H.,S04 it dis- solves with a violet-blue colour. — KA'2aq:red glistening plates, al. sol. hot, v. si. sol. cold, water, dyes silk, wool, and cotton a brownish, red (Griess, B. 16, 2035). Amido-sulpho-naphthalene-azo-diphenyl-rzo- naphthylarnine sulphonic acid [1:4:2] C10HS(NH2)(S03H)-N2-CBH4. [1:4:2] C10H5(NR2)(SOSH)- N2-C.HS. Formed by combining diazotised benzidine with (a)-naphthylamine ^-sulphonic acid. Dyes cotton from an alkaline bath scarlet, turned blue by a trace of acid. The aqueous solution is readily reduced by NFL, and zinc-dust, giving benzidine and naphthylene-o-di-amine sulphonic acid (Witt, B. 19, 1719). Benzene-azo-m-diamido-benzene-azo-benzene CBHS— N2-C(jH2(NH)2— N2— CUHS. [250°]. Formed by the combination of diazobenzene with chrysoi'dine. Dark red needles or six- sided plates. Sol. hot chloroform and benzene, v. si. sol. alcohol and ether, insol. water. Weak base. Salts. — B'HCl: violet-brown amorphous solid. -B'.,H2Cl2PtCl,: violet-brown amorphous pp. (Griess, B. 16, 2028). B nzene-azo-w-diamido - benzen e-azo-benzene ;i-sulphonic acid C6H4(S08H) -N2- C6H2(NH2)2— N2— C,HV Formed by the action of ^-diazo-benzene-sul- phonic acid on chrysoidine. Dark-brown mi- ' croscopic crystals. V. si. sol. alcohol, insol. WSAZO- COMPOUNDS. 4J7 ether. A.'K : reddish-bro'vn plates, sol. hot, si. sol. cold, water (Griess, B. 16, 2J32). Benzene - azo - di - amido - benzsne-azo-benzoic acid CbH,(CO.H) -N2— C,H,(NH.,),— N2— CdH,. Formed by combining m-diazo-benzoic acid with chrysoiidine (Grieas, B. 16, 2032). Brownish- red powder. Insoluble or nearly insoluble in all ordinary solvents. Soluble in alkalis with a brownish -red colour. (aJ-Benzene-azo-TO-di-amido-benz^ne-azo-tolu- ene C^— N2-CSH,(NHV!)2— N2— C;H7. [192°]. Formed together with a small quantity of the (S)-isomeride by the combination of p-diazo- benzene with p-toluene-azo-phenylene-diamine. Dark-red glistening needles. Sol. ether, chloro- form and hot benzene, insol. water and alcohol. (#) -Benzene- azo-ro-di -amido -benzene- azo- tol aene CSH, - N2— C6H,(N H,)2- N2— C7H7. [225°]. Slender yellow needles. Sol. alcohol and ether, v. si. sol. chloroform, sol. in water (Griess, B. 16, 2029). Benzene - azo -m-di- amido -benzene-^?- azo- toluene C7H,— N,— C.H^NH,)., -N2— CdH,. [214°]. Formed by the combination of p-diazo- toluene with chrysoidine (Griess, B. 16, 2030). Dark-red glistening needles. SI. sol. chloroform, ether, and benzene. Benzene-azo-benzene-azo-p-cresol (4) (1) <S) (2) CtiHs— Nj-C^-N,— C6H3(CH:,)(OH). [160°]. Obtained by the action of diazo-benzene-azo- benzene chloride (by diazotising benzene-azo- aniline) on an alkaline solution of p-cresol (Nolting a. Kohn, B. 17, 354). Small brown needles. SI. sol. alcohol, m. sol. chloroform, benzene, and acetic acid. Dissolves in H2S04 with a reddish violet colour. Benzene-azo-b<mzen«?-azo-ethyl-(6)-naphthyl- amine C6H,-N2— CliH4— N2— C^H^NHEt. [142°]. Small red needles. Formed by heating ethyl-(£)-naphthyl-nitrosamine with an acetic acid solution of benzene-azo-aniline (Henriques, B. 17, 2670). Benzene azo-^enzene-azo-(|8)-naphthol C_.H,— N2— C,iH4— N2— CIOH6.OH. From diazo- tised benzene-azo-aniline and (j8)-naphthol (Nietzki, B. 13, 1838). Brick-red powder. Benzene-azo-benzene-azo-resorcin CoH, -N2-CBH,—N2— 0^(0^).,. By the action of diazotised benzene-azo-aniline on resorcinol two isomerides are formed which are separated by their different solubilities in aqueous alkalis. (a)-Compound [184°]. Brownish red powder consisting of microscopic tables. Dis- solves with a carmine red colour in aqueous NaOH and in H2S04. Sol. alcohol, ether, and chloroform. (ff)-Compound [215°]. Brown powder. Dis- solves in alcoholic NaOH with a violet-blue colour and in H,S04 with a pure blue colour, v. si. sol. alcohol, ether, and chloroform, insol. aqueous NaOH (Wallach, B. 15, 2817). Benzene-azo-methyl-pyrrol-azo-benzene C8Hj— N,— C4H.,NMe— N2— C6HS CsHs.N2.g=CH probably NMe| [196°]. Formed by CBHiN2.C=CH the methylation of benzene-azo-pyrrol-benzene. lied plates (O. Fischer a. Hcpp, B. 19, 2253). VOL. I. Benzene-azo-oxy-banzeae-azo-benzene (1) (4) (3) C.H,— N2- CBH.,(OH)— N,— C8H5. Benzene- disazo-phenol. Phenol-bi-diazo-benzene. [131°]. Formed, together with benzene-azo-phenol, by treating diazo-benzene nitrate with BaC03 in the cold, or by the action of diazo-benzene nitrate upon a solution of benzene-azo-phenol in KOHAq (Griess, A. 137, 86; B. 9, 628). Brown lustrous needles or plates (from alcohol). V. si. sol. water, v. sol. KOHAq, v.sl. sol. NH,Aq, insol. Na2C03Aq. Methyl ether 018H,3N4(OMe) [110°], small yellow crystals, v. sol. ether, benzene, acetone, and hot alcohol. Acetyl derivative C.gH^N^OAc) [116°], small yellow needles, sol. alcohol, ether, and benzene. Benzoyl derivative CI9H13N4(OBz) [139°], small yellow needles, si. sol. cold alcohol (Nolting a. Kohn, B. 17, 368). Benzene-azo-di-oxy-benzene-azo-benzene C.H,— N,-C((H2(OH)2— N,— CJi,. By the action of diazo-benzene chloride on an alkaline solution of benzene-azo-resorcin two isomerides are formed which are separated by their solu- bility in aqueous alkalis. A third isomeride (7)- is formed, together with benzene-azo-resorcin, by the action of diazo-benzene chloride on res- orcin treated with KOH (1 mol.) in dilute aqueous solution. (a)-Gompound [215°]. Brown felted needles. Dissolves easily with a red colour in aqueous NaOH and in BLjS04. SI. sol. alcohol and ether, m. sol. chloroform. Its di-acetyl derivative forms brown glistening needles, [184°] (Wallach). (ft)-Compound [220°]. Microscopic needles. SI. sol. alcohol and chloroform, insol. aqueous NaOH. Dissolves in H2S04 with an indigo-blue colour, and in alcoholic NaOH with a red colour (Wallach, B. 15, 2816). (y)-Compound [222°]. Large red needles. Sol. chloroform, v. si. sol. alcohol. It dissolves in strong alkalis with a brownish -yellow colour; in H.[SO4 with the same colour. By tin and HC1 it is reduced to aniline and di-amido- resorcin. Di-acetyl-derivative ClgH,,N4(OAc)2 [138°], orange needles (Lieber- mann a. Kostanecki, B. 17, 880). Benzene-azo-trioxybenzene-azo-benzene C6H?— N2— C6H(OH)3— N2— C6H5. Phloroglucin- bi-diazo-benzene. Yellowish-brown leaflets. Pre- pared by the action of diazobenzene nitrate on phloroglucin (Weselsky a. Benedikt, B. 12, 226). Benzene-azo-dioxy-benzene-azo - naphthalene C6HS— Nj— CSH2(OH)2— N2— CIOH7. [155°]. From diazo-benzene chloride and an alkaline solution of m-di-oxy-benzene-azo-naphthalene (Wallach, B. 15, 22). Benzene-azo-di-oxy-benzene-azo-toluene CBHS— N2-C6HXOH)2— N2- C8H,(CH3) [1:4]. Prepared by the action of diazo-benzene chloride on an alkaline solution of m-dioxy-benzene-azo- toluene, or of diazo-toluene chloride on an alka- line solution of benzene-azo-resorcin ; in either case the same three isomerides are simultane- ously produced and are separated by means of their different solubilities. (a)-Compound [196°]. Golden brown needles. Dissolves with a red colour in H ,SO, and NaOH. EE 418 DISAZO- COMPOUNDS. Sol. alcohol and chloroform. Its di-acetyl- derivative forms yellow needles, [176°]. (a')-Compound [241°]. Dissolves with a red colour in H2SO4 and in aqueous NaOH. Its di-acetyl-derivative forms yellow needles, [196°]. (&)-Compound [206°]. Brownish - black microscopic crystals. Insol. aqueous NaOH, dis- solves in H2S04 to a blue solution. SI. sol. alco- hol, m. sol. chloroform (Wallach, J3. 15, 2821). Benzene-azo-oxy-cymene-azo-benzene (2) (1)(4) (3) (5) C8H5— N2— C8HMePr(OH)— N2— CSH5. Thymol- bi-diazo-benzene. [168°]. Formed, together with benzene-azo-thymol, by the action of diazo- benzene on thymol (Mazzara, G. 15, 52, 228). Silky needles, sol. chloroform. By reduction with tin and HC1, and subsequent treatment with Fe-jClg, it is converted into oxy-thymoquinone. Benzene-azo-o-oxy-toluene-azo-benzene (i) (3) (4) (5) C6HS— N2— CsH2Me(OH)— N2— C6H5. [115°]. Ob- tained by the action of (2 mols. of) diazo- benzene chloride on an alkaline solution of o-cresol (Nolting, B. 17, 364). Beddish-brown plates. V. si. sol. cold alcohol. Dissolves in alkalis with a yellowish red colour. Acetyl derivative [121°], yellow needles, v. sol. alcohol, ether, and benzene. Benzene-azo-w-oxy-toluene-azo-benzene (1) (2) (4) (3) C«HS— N,— G.ftMefOH) -N2— C6H5. [149°]. Ob- tained by the action of (2 mols. of) diazo- benzene chloride on an alkaline solution of w-cresol. Beddish-brown plates. Sol. ether, benzene, and hot alcohol, si. sol. cold alcohol. Acetyl derivative [157°], small yellow- ish-brown needles (Nolting a. Kohn, B. 17, 367). Benzene-azo-di-phenyl-urea-azo-benzene C8HS— N2— C8H4.NH.CO.NH.C6H4— N2— C6HS. [270°]. Formed by the action of carbonyl chloride on benzene-azo-aniline (Berju, B. 17, 1404; C. C. 1884, 871). Small plates. Sol. chloroform and benzene, si. sol. alcohol. Benzene-azo-di-phenyl-thio-urea-azo-benzene C8HS— N2— C6H4.NH.CS.NH.C6H4— N2— C6H5. [199°]. Formed as a by-product of the action of phenyl-mustard oil on benzene-azo-aniline (Berju, B. 17, 1405). 81. sol. hot chloroform, xylene, and acetic acid, v. si. sol. alcohol, ben- zene, and CS2. Benzene-azo-pyrrol-azo-benzene C8Hs-N2-C4H,N-N2-C8H5f C8H5.N2.C = CH probably NH | . [131°]. Obtained C6H5.N2.C = CH by combining (2 mols. of) diazo-benzene chloride with (1 mol. of) pyrrol in alkaline solution. Bed crystalline solid. Sublimable. M. sol. ethej; and benzene, si. sol. alcohol, nearly insol. wateV. Possesses basic properties. Dissolves in dilute HC1 with a reddish-yellow colour ; in cone. ILjS04 with a splendid blue colour. Its alcoholic solution is turned magenta-red by NaOH, reddish-violet by cone. HC1 (0. Fischer a. Hepp, B. 19, 2251). Benzene-azo-pyrrol-(0)-azo-naphtlialene C6H5-N2-C4H3N-N2 -C10H7 C8H4.N2.C = CH probably NH | . [151°]. Formed C1.H..N.iC = CH by the combination of diazo-benzene chloride with pyrrol- (0) -azo-naphthalene or of (/3)-diazo- naphthalene diloride with pyrrol-azo-benzene, in alkaline alcoholic solution. Bed plates, with bluish reflection. SI. sol. alcohol (O. Fischer a. Hepp, B. 19, 2256). Tri - bromo - benzene - azo - di - phenyl - di- isoindole-azo-tri-bromo-b ^nzene C6H4-N.-C,,H,,Br, N C40H24NeBr8 or CLH s.c-c H HC-CC6HS N C8H4— N2— C6H,Brs [150°]. Orange yellow prisms. Soluble in most ordinary solvents except water. Formed by the action of tri-brotno-diazo-benzene chloride on di - phenyl - di - iso - indole. — B"H;C12 : slender yellowish-brown needles (Mohlau, B. 15, 2490). Di - bromo - oxy - benzene - azo - di - phenyl - di- isoindole-azo-di-bromo-phenol. C6H<— N2-CdH.Br,(OH) N CfiH6C CH C4uH2)iN<iBr402or | | HC CC.H,, V CdH4— N2— C6H,Br,(OH) [198°]. Yellowish-green prisms. Soluble in alcohol, dyes wool orange and silk yellow. Formed by the action of di-bromo-diazo-phenol on di- phenyl -di-isoindole. — B"H._,C12: short metallic glistening prisms, insol. water (Mohlau, B. 15, 2492). i|/ . Cumene - azo - m - di - oxy -benzene • azo - <|/- cumene C6H2Mes— N2-C6H2(OH)2— N2— CBH2Mes. Formed, together with cumene-azo-resorcin, by combining diazo-cumene chloride (from amido-pseudo-cumene [62°]) with resorcin (Liebermann a. Kostanecki, B. 17, 882). Small red needles. Dissolves in H2SO4 with a red colour. Insoluble in alkalis. p-Di-methyl - amido - benzene -p-azo - benzene- azo-(/3)-naphthol HO.C,0H8— N2— C^H,— N2— C6H4.NMe2. [210°]. Got by pouring a diazotised solution of p-amido- benzene-azo-dimethylaniline hydrochloride into a solution of (j3)-naphthol in NaOH (Meldola, C. J. 45, 109) Bronzy green needles. SI. sol. alcohol, v. sol. hot C2H4O2, benzene, and chloro- form. Solutions in the above solvents are red ; in alcoholic NaOH, red ; in cone. H2S04 green, turned blue by dilution. An alcoholic solution is turned blue by HC1. p- Di-methyl-amido-benzene-^i-azo benzene- azo-(a)-naphthol HO.C1(1H6.N2.C6H4.N2.C6H4NMe2. Prepared like its (/9) isomeride (M.). Its properties are similar, except that the solution in alcoholic KOH is violet. It decomposes below 200°. DISAZO- COMPOUNDS. 41 n Di-methy] - amido -benzene - azo - bsnzene-azo- resorcin (HO)2CliH3— N2— C0H,— N,— CtfH,.NMer Brown powder. Decomposed before melting. 81. sol. boiling alcohol, the solution being reddish- orange and turned first violet, then blue by adding HC1. SI. sol. glacial acetic acid, the solution being red when hot, violet when cold. Insoluble in toluene. Solution in alcoholic KOH is reddish-violet. Solution in cone. H2S04 is violet, becoming blue on dilution (Meldola, C. J. 45, 110). Di-methyl-amido-benzene-p-azo-benzene-azo- phenol HO.CdH4— N2— CdH4— N2— C_H ,NMe2. Brown powder, forming a brown solution in aqueous KOH, and a red solution in alcoholic KOH. Kesembles the analogous di-methyl-amido- benzene - p - azo - benzene - azo - resorcin (q. v.) (Meldola, C. J. 45, 111). Di-me thyl - amido - benzene - azo - toluene - azo- (0)-naphthol (2) (l) (4) CaH^NMe,)— N,— C6H:(Me— N,— C^H^OH. From diazotised di-methyl-amido-benzene-azo- p-toluidine and (fl)-naphthol (Wallach, A. 234, 858). Bed needles (from chloroform), insol. water. Di-methyl-am '. do - benzene - azo - tolue ne - azo - phenol <3) (l) (4) CH,(NMe,)— N2-C,,H3Me— N2— C0H4OH.ri60°]. From diaz'otised C.H^NMe..)— N,— CljHiiMeNH2 and phenol (Wallach, A. 234, 357). Orange needles. (a) - naphthalene - azo - pyrrol - (a) - azo - naphthalene C1QH,-N2— C4H,NH— N2— C10H7, C10H7.N2.g=CH probably NH |. C10H7.N2.C=CH Formed by adding (o)-diazo-naphthalene chloride (2 mols.) to an alkaline solution of pyrrol (1 mol.). Metallic-glistening needles. Sol. alcohol with a dark yellowish-red colour. Dissolves in cone. H2S04 with a blue colour (0. Fischer a. Hepp, B. 19, 2255). (0) -Naphthalene-azo-pyrrol- (0) -az o-n aphthal- ene CIt>H7-N2-C4H.,NH— N2-C10H,. CIOH7.N2.C=CH probably NH | . [288°]. Formed by C10H7.N2.C=CH adding (j8)-diazo-naphthalene chloride (2 mols.) to an alkaline solution of pyrrol (1 mol.). Glistening coppery plates. SI. sol. alcohol. The alcoholic solution is turned reddish-violet by cone. HC1. Dissolves in cone. EL^SO., with a blue colour (0. Fischer a. Hepp, B. 19, 2255). nt-Nitro-benzene-p-azo-benzene - (o) -azo - (£) - naphthol N02CSH4 -N2— C6H4— N2— CIOH6.OH. [c.218°]. From diazotised NOa.C<fH4.N2.C(iH4.NH2 and (£)-naphthol. Small yield (Meldola, C. J. 45, 113). Orange crystals with green lustre. Solutions in C,,H,O2 and in toluene are orange ; in alcoholic NaOH, violet ; in cone. HjS04 green, turned blue on dilation. m-Nitro-benzene-(a)-azo-naphthalene-(a)-azo- (a) -naphthol NO,.C8H4— N2— CIOHg— N2-C10Hg.OH. A dark amorphous powder. Solutions in toluene, chloro- form and glacial acetic acid are red ; in cone. H2S04 dark indigo violet, becoming blue on dilution ; in alcoholic potash, greenish-blue (Meldola, C. J. 45, 116). m-nitro-ben3ene-(a)-azo-naphthalene-(a)-azo- (/3)-naphthol NO,.C,,H,— N,— C.oH,— N2— C10Htt.OH. From m-nitro - benzene - (a) - azo- (a) - naphthyl - amine by diazotising and treating with (£)- naphthol (Meldola, C. J. 45, 115). Minute bronzy needles (from toluene). Blackens at 245°. Insol. alcohol or glacial acetic acid. Solu- tions in chloroform and in hot aniline are violet ; in toluene red when hot, reddish-violet when cold ; in boiling alcoholic KOH, blue ; in cone. H,jSO4, olive colour, on dilution, blue and then violet. m-nitro - benzene- (a) - azo - naphthalene - azo - resorcin NO2.C,.H4— N2— C10H6— N2— C0H?(OH).,. Bronzy powder, not very soluble. Solutions in boiling alcohol are reddish ; in glacial acetic acid, toluene and chloroform, orange; in aqueous or alcoholic KOH, blue ; in cone. H2S04, green, changing to bluish-green on dilution (Meldola, C. J. 45, 116). p- Nitro- benzene-azo-m-xylene-azo- (o) -naph- thol N02.C8H4— N2— C^Me.,— N2— C10H,..OH. Preparation and properties are similar to those of the preceding (0) -compound. Sulphonic acid NO2C6H4— N2— C6H.2Me2— N,— C,0H5(S03H)(OH) Similar to the corresponding (0) -compound, but dyes reddish-brown. p - Nitro - benzene - azo - m - xylene - azo - /3 - naphthol N02.CSH4— N2— C6H2Me2— N2— CIOHti.OH. [278°]. From N02.C6H4— N2— CsH.jMe.NH2 by diazo- tising and treating with sodium (£) -naphthol (Meldola, C. J. 43, 434). Green scales (from toluene). Scarcely soluble in alcohol or glacial acetic acid. Forms a crimson solution in boil- ing aniline or nitrobenzene, and a green solution in cone. ELjS04, turned violet by dilution. Sulphonic acid N02.C6H4.N2.06H2Me2.N2.CIOHi(OH)S03H. Gotby using C)0H6(OH)SOSH. Dyes claret-red. p-Nitro-benzene-azo-w-xylene-azo-phenol N02.C6H4— N2— C6H.,Me2— N2— C6H4.OH. Orange powder. 81. sol. alcohol and benzene, v. sol. hot aniline. Solutions are orange. Solution in alcoholic NaOH is reddish-violet. Solution in cone. H^SO, is blue (Meldola, C. J. 43, 436). p-Nitro-benzene-azo-m-xylene-azo-resorcin NO.,.C8H4— N-j-C^Mej— N2— CdHs(OH)2. [231°]I Brown powder. Forms orange solutions in boiling alcohol, toluene, and glacial acetic acid. Solution in alcoholic NaOH is red, turned violet by excess of NaOH. Cone. H2S04 forms a blue solution (Meldola, C. J. 43, 436). jp-0xy-benzene-jp-azo-benzene-(o)-azo-(a)-naph- thol C.H4(pH)-N2— CSH4— N2— C.^.OH. From diazotised p-amido-benzene-azo-(a)- naphthol and an alkaline solution of phenol (Meldola, C. J. 47, 665). Dark amorphous powder. Its solution in cone. HjSO4 is indigo- blue; in boiling toluene, orange; in alcohol, red ; in KOHAq, dull red ; and in alcoholic NaOH, deep claret colour. p - Oxy- benzene -p • azo - benzene-(o)-azo-(3)- naphthol HO.C8H4— N2— C8H4— Nj— C10H.(OH). [225°]. From jj-amido-benzene-azo (0) -naphthol by diazotising and mixing with an alkaline solution of phenol (Meldola, C. J. 47, 666). Red warty concretions. Its solution in cone. H2SO4 is bluish-green, and becomes violet on dilution. BE 2 450 DISAZO- COMPOUNDS. Its solution in boiling toluene, or boiling alcohol. is red. Its solution in KOHAq is reddish-violet. m-Di-oxy -benzene -2)-azo-benzene-(o)-azo-(a)- napbthol [4:2:1] C6Hi(9H),— N2-C6H4-N2-C10Htt(OH). Formed by mixing diazotised p-amido-benzene- azo-(o)-naphthol with a solution of resorcin in dilute NaOH (Meldola, C. J. 47, 665). Bronzy- green powder ; si. sol. toluene and acetic acid, forming a red solution. Its solution in KOHAq is blue ; its solution in NHsAq is violet. It is decomposed by heat without fusion. m-Di-oxy-benzens -p-azo-benzene-(a) -azo- (j8) - naphthol [4:2:1] CSH3(OH)2-N2— C8H4— N2-C)0H6.OH. From diazotised ^-amido-benzene-azo-(JB)-naph- thol and an alkaline solution of resorcin (Meldola, C. J. 47, 666). Bronzy-green powder. Its solu- tion in cone. H.^S04 is deep bluish-green ; in dilute aqueous alkalis, violet. 81. sol. toluene forming a red solution. m-Oxy-beuzene-azo-benzene-p-azo-phenol [3:1] HO.C6H4— N2— CgH,— N2— C6H4.OH [1:4]. Dark powder. Easily soluble in alkalis. Formed by diazotising amido-benzene-w-azo-phenol (CgH4(OH)— N2— C8H4.NH.,) and combining it with phenol (WaUach a. Schulze, B. 15, 3021). p-Oxy-benzene-azo-benzene-p-azo-phenol [4:1] HO.CsH,— N2— CgH,— N2— CfiH4.OH [1:4]. [o. 207°]. From diazotised amido-benzene-p- azo-phenol and a solution of phenol in dilute alkali (Meldola, C. J. 47, 660). Amorphous brown powder. Its solution in cone. H2SO4 is violet, unchanged on considerable dilution ; v. sol. NH,Aq and KOHAq forming a red solution ; insol. boiling toluene ; forms an orange solution in hot phenol or aniline. m - Di . oxy - benzene -p-tao- benzene - az o - r e - sorcin [42:1] C.H,(OH)t— N.— C.H.— N,— C.H,(OH), [1:2:4]. From diazotised #-amido-benzene-azo-resorcin and an alkaline solution of resorcin (Meldola, C. J. 47, 661). Dull bronze-like powder, v. si. sol. alcohol, insol. toluene. Its solutions in cone. H2S04 and in alkalis are violet. Oxy - carboxy - benzene - azo - benzene-(a)-azo- (£)-naphthol (4) (3) (1) (4)(a) 03) CsH^COoHXOH)— N2— C6H4— N:N— C10H6(OH). [above 255°]. From diazotised p-amido-benz- ene-azo-salicylic acid and an alkaline solution of (0)-naphthol (Meldola, C. JA1, 668). Minute brown needles (from boiling aniline). V. si. sol. boiling toluene, si. sol. alcohol and glacial HOAc. Its solution in cone. H.,S04 is greenish- blue, changing to violet on dilution. Its solu- tion in KOHAq is reddish-violet. Oxy - cymene - azo - tri - pbeny 1 - methane • az o - thymol [63:4:1] C.HJ,te!>r(OH)-N,-C.IW pTTp. [63:4:1] C.H,MePr(OH)— N.— C.H.^ ourt1' [170°]. Formed by mixing diazotised diamido- tri-phenyl-methane hydrochloride with an alka- line solution of thymol (Mazzara, Q. 15, 44). Amorphous black powder. After reduction and oxidation it gives thy moquinone. (a) - Oxy - naphthalene -p - azo - benzene - (a) - naphthol (a) (a)(4) (l)(a) (a) C10H6(OH)-N:N-C6H4-N:N-CIOH6(OH). Formed by diazotising p - amido-benzene-azo- (a) -naphthol and mixing the product with an nlkaline solution of (a) -naphthol (Meldola, C. J. 47, 664). Green lustrous powder; v. si. sol. glacial HOAc, alcohol, and toluene, m. sol. boiling aniline, forming a red solution. Its solution in NaOHAq is blue, in cone. H.SO, blue, turned violet on dilution. With Ac^O and NaOAc it forms on heating a di-acetyl derivative. (i8)-0xy-(a)-naphthalene -p - azo - benzene-(a)- azo-(£) -naphthol (/S) (aXl) (4)(a) (ft) C10H8(OH)— N:N— C6H4— N:N— C10Ho(OH). [over 275°]. From diazotised p-amido-benzene- azo-(£) -naphthol and an alkaline solution of (£)- naphthol (Meldola, C. J. 47, 664). Dull bronzy powder, or green needles (from hot aniline). Insol. boiling alcohol, or NaOHAq ; sol. cold alcoholic NaOH, forming a violet solution. SI. sol. hot toluene forming a magenta solution. Cone. H-jSO., forms a blue solution, turned violet on dilution. (a) - Oxy -naphthal ene - p- azo - benzene-azo- (/3) - naphthol (a) («)U) (4)(a) (0) CIOH6(OH)-N:N— C6H4— N:N— C10H8(OH). [236°]. From diazotised p-amido-benzene-azo- (a) -naphthol and an alkaline solution of (£)- naphthol (Meldola, C. J. 47, 665). Dull bronzy powder, v. si. sol. boiling alcohol ; m. sol. boil- ing toluene and glacial acetic acid forming violet solutions ; cone. H^SO^ forms a blue solu- tion, becoming violet on dilution. (a)-0xy-naphthalene^p-azo -benzene -azo- (£)- naphthol-di-sulphonic acid (a) (a)(l) (4) (0) C,0H.(OH)— N:N-C.H4— N:N— C.oH^SO.HX.COH). From diazotised p - amido - benzene - azo - (a)- naphthol and an alkaline solution of (£)-naphthol di-sulphonic acid. Its sodium salt is violet and gelatinous; it is an indigo-blue dye (Meldola, C. J. 47, 665). (0) - Oxy - naphthalene - azo - benzene - azo-(0)- naphthol di-sulphonic acid. Is similar to the last body, but of greater stability (M.). Oxy-di-sulpho-naphthalene-azo-benzene-azo- (0) -naphthol di-sulphonic acid 01?H4(SOJH)>(OH)— N,— C.H.— Na— 010H4(SO,H).,(OH). Glistening greenish needles. Dyes wool and silk a deep indigo-blue, which, however, is very unstable to light. Is prepared by diazotising the mono-acetyl derivative of j)-phenylene-di- amine and combining it with (£) -naphthol-di- sulphonic acid (modification insoluble in spirit), the product C6H4(NHAc).N2.C10H4(OH)(S03H)2, which is a scarlet colouring matter, is saponified, diazotised, and again combined with (#) -naph- thol-di-sulphonic acid (Nietzki, B. 17, 344; 1350). Fhenyl - amido - benzene -p - azo - benzene-azo- (j3) -naphthol HO.C10H4— N2— C6H4— N2— CtjH4NHC6H5. [204°]. From ^-amido-benzene-azo-di-phenyl- amine by diazotising and adding sodium (0)- naphthol (Meldola, C. J. 43, 442). Warty scales with bronze lustre. 81. sol. boiling alcohol, v. sol. benzene. The solutions are red. In glacial acetic acid the solution is red when hot, violet when cold. Solution in cone. H.2SO4 is greenish- blue, solution in alcoholic KOH is red but turned blue by HC1 (characteristic). Fhenyl - ethyl - amido - benzene • azo-benzene- azo-(3)-naphthol HO.C10Hg— N2— C6H4— N2-CljH4.NEt.C6Hs. DISAZO- COMPOUNDS. 421 From p-diazo-nitro-benzene by combining with ethyl-cli-phenyl-amine, reducing with ammo- nium sulphide, diazotising the product and treating with (B) - naphthol. Bronzy powder. Solutions in alcoholic EOH, alcohol, and ben- zene are red ; in cone. H.,S04 indigo-blue, turned bright blue on diluting. HC1 turns the alcoholic solution blue (Meldola, C. J. 45, 111). p - Sulpho - benzene - azo - benzene - azo - (£)- naphthol-(/3)-sulphonic acid (4)_ (1)(1) (4)(o) (8) (fl) C.H4(SO,H)— N :N-C.H4— N :N—CleH.(SO,H)(OH). From diazotised p-amido-benzene-azo-benzene sulphonic acid and an ammoniacal solution of sodium (0) -naphthol ' a '-sulphonic acid (Bayer a. Co., B. 15, 1351). The sodium salt is a scarlet dye (croceine scarlet). Cone. H2S04 forms a blue solution. The absorption spectrum has been studied by Hartley (C. J. 51, 195). p-Sulpho - benzene -azo -benzene - azo -tolylene diamine C6H4(S03H)— N.2-C6H4— N2— C7HS(NH2)2. Bed- dish-brown microscopic needles. Formed by combining diazo-benzene-azo-benzene-jj-sul- phonic acid with tolylene -diamine (Griess, B. 16, 2036). Sulpho -benzene-azo- di-phenyl-di-isoindole- azo-benzene sulphonic acid C(jH4-N,-CdH4(S0llH) A C6HSC — CH C4QH30N6Sz08or | | Formed by the action of diazo-benzene-sulphonic acid on di-phenyl-di-isoindole. Metallic glisten- ing brown scales. Very slightly soluble in all solvents. Dyes silk and wool nearly the same shade as chrysoidine. On reduction it gives sulphanilic acid and di-amido-di-phenyl-di-iso- indole. Salt s. — A"Naj aq : yellow plates. — A"Ag2 : red prisms (Mohlau, B. 15, 2495). bulpho - benzene-azo- sulpho-benzen e-(a)-azo- (|B) -naphthol C.H^SO^H)— N2— C.ftfSO.H)— Na-C10H8.OH. From diazo-sulpho-benzene-azo-benzene sul- phonic acid and an alkaline solution of (/3)- naphthol (Nietzki, B. 13, 800). The sodium salt is a red dye (Biebrich scarlet). Cone. HjS04 forms a green solution. Its absorption spectrum has been studied by Hartley (C. J. 51, 194). Sulpho - benzene - azo-sulpho - benzene - (0) - azo-naphthyl-p-tolyl-amine (' Wool-black ') CgH4(SO,H).NJ.C6H3(SOsH).Nlt.C10H7.NHC7H7. The coml. product is a bronzy powder. V. sol. hot water with a violet-blue colour. Dissolves in cone. HjSO4 with a deep indigo-blue colour. Formed by combination of diazotised amido- sulpho-benzene-azo-benzene-sulphonic acid with y-tolyl - (ft) - naphthylamine. By boiling with moderately dilute H.,SO4 it is decomposed into tolu-(a0)-naphthazine [1693] and amidoazo-benz- ene-di-sulphonic acid : C.H4( SO.H)— N,— C.H.< SO.H)— N,— C,»HrNHCTH,= C,.H.<( ' "XH.+C.H4(SO,H)--N.-C.H.(NHt)(SO.H). \N^ The Ca and Ba salts are insoluble black pps. (Witt, B. 20, 579). p-Toluene - azo-m - diaraido - benzene - azo - (£)- naphthalene C,H7— N2— C6H2(NH,)2— N,- C10H7. Formed by the combination of jp-diazo-toluene with (0)-naphthalene-azo-7?t-phenylene-diamine (Griess, B. 16, 2031). Small red glistening plates. V. sol. chloroform. 2>-Tolnene-azo-ethyl-pyrrol-p-azo-toluene C,H7-N3— C4HaNEt— N2— C;H7, C6H4Mo.N2.Q=CH probably NEt| [180°]. C8H4Me.N2.C=CH Formed by ethylation of toluene-azo-pyrrol-azo- toluene; or by combining diazo -p- toluene chloride (2 mol.) with ethyl-pyrrol (1 mol.) in alkaline solution. Steel-blue needles. 81. sol. alcohol (O. Fischer a. Hepp, B. 19, 2254). Toluene-azo-dioxy-benzene-azo-toluene C7H7— N2— C6Hjj(OH)2— N2— C7H7. By the action of jp-diazotoluene chloride on an alkaline solu- tion of p-toluene-azo-resorcin two isomeridea are formed which are separated by their dif- ferent solubilities in alkalis. (a)-Compound [256°]. Yellow felted needles. Spanngly soluble in alcohol and cold chloroform. (B) - Compound [203°]. Brownish - black microscopic needles (Wallach, B. 15, 2825). Tolnene-azo-trioxybenzene-azo-toluene C6H4Me— N2— C6H(OH)3— N2— C6H4Me. Long red needles. Prepared by the action of diazo- toluene nitrate on phloroglucin (Weselsky a. Benedikt, B. 12, 227). Toluene-azo-pyrrol-azo-toluene C7H7— N2— C.H.jNH- N2— C7H7, C6H4Me.N2.0=CH probably NH | . [179°J. C6H4Me.N2.C=CH Formed by adding (2 mols.) diazo-^p-toluene chlo- ride to an alkaline solution of pyrrol (1 mol.). Red prisms with steel-blue reflex. 81. sol. alcohol. Its alcoholic solution is turned reddish- violet by cone. HC1. Dissolves in cone. H2S04 with a blue colour (0. Fischer a. Hepp, B. 19, 2254). Toluene-o-azo-tolnene-azo-(a)-naphthol (4) (1) (5) (2) (a) C9H4(CHJ-N2-CSH,(CHS)-N2-C10HS(OH), XN— N— CJOH.(OH) or CgHJCHX I | . [210°]. \N-N-C8H4(CH,) Formed by combination of o-diazo-azo-toluene with (a)-naphthol. Brownish-red needles (from aniline). 81. sol. ordinary solvents. In sol. aqueous NaOH, sol. alcoholic NaOH with a violet-red colour. By SnCl, it is slowly reduced to amido- (a) -naphthol and tolyl-azimido-toluene C7H6:N3.C7H7, together with small quantities of p-toluidine and tolylene-o-diamine (Zincke a. Lawson, B. 20, 1178). Toluene-o-azo-toluene-azo-(y8)-naphthol (4) (1) (5) (2) (fl) CBH4(CH,)-N2-C6H3(CH3)-Na-C10H6(OH),or ,N— N— C..HJOH) CVH^CHX I I \N-N-CSH4(CH3) [177°]. Formed by combination of o-diazo-azo-toluene with (/3)-naphthol. Long dark-red four-sided prisms, with green reflex. V. sol. benzene, and chloro- form, si. sol. alcohol, acetone, and petroleum- Dissolves in alcoholic NaOH only slightly. 422 DISAZO- COMPOUNDS. By SnCLj it is reduced to (a)-amido-(6)-naphthol and tolyl-azimido-toluene C7H,.:N3.C7H;, together with small quantities of jp-toluidine and tolylene- o-diamine (Zincke a. Lawson, B. 20, 1179). Toluene-p-azo-toluene-azo-3-naphthol (1) (3) (4) C/3) [186°]. Formed by combination of £>-diazo-azo- toluene with (jS)-naphthol. Deep-red needles. V. sol. hot alcohol and benzene. By SnCl2 it is easily reduced, giving (a)-amido-(j8)-naph- thol, o-toluidine, and tolylene - p - diamine CdH:(Me(NH2)2 [1:2:5] (Zincke a. Lawson, B. 20, 1182). To 1 u en e -o - azo - toluene - azo - (0) - napbthyl - (4) (1) (5) (2) (0) amineC6H4(CHs).N.!.C6H3(CH.1).N,.C10H6(NH2),or the corresponding hydrazimido- formula. [203°]. Formed by combination of o-diazo-toluene-azo- toluene with (/3) - naphthylamine. Deep-red glistening plates. V. sol. benzene and chloro- form. By SnCLj it is reduced to tolyl-azimido- toluene C7H8:NSC.H, and (probably) naphthyl- ene-o-diamine (Zincke a. Lawson, B. 20, 1180). AZO- COMPOUNDS, TERTIABY. Oxy-benzene-p-azo-benzene-(a)-azo-naph.thal- ene-azo-phenol HO.CA— N,— O.H4— N,— O10H.— K,— C.H4.OH. From NH^CgHj— N2— CioHg.NHj by diazotising and adding sodic phenate (Meldola, C. J. 43, 439). Dull bronzy-green powder. Forms orange solutions with boiling aniline or toluene. Solution in alcoholic KOH is violet; in cone. ELjS04, indigo-blue. Di-oxy-benzene-p-azo-benzene-(a) - azo - naph- thalene-azo-resorcin ( HO),C.H,— N,— C.H4— Ka— qioH.— K,— C.H,(OH >, Brown powder. Its solutions are dull red in alcohol, violet in alcoholic KOH, bluish-green in cone. H;SO4. (/3) - oxy - naphthalene-p-azo-benzene-(a) -azo- naphth.alene-azo-(j3)-naphthol HOA.H.— Na— C.H.— N,— O..H.— N.— O^H.-OH. Formed by diazotising amido-benzene-azo-(£). naphthylamine NH2.C6H4.N2.C10H6.NH2 and treating with an alkaline solution of (/3)-naphthol (Meldola, C. /. 43, 437). The pp. may be separated by crystallisation from hot aniline into two modifications, one remaining in solu- tion, the other separating as needles with green lustre. Crystalline form [c. 295°]. Insoluble in boiling alcohol, acetone, or glacial acetic acid, hardly soluble in chloroform or benzene. Forms violet solutions with aniline or nitrobenzene. Solution in cone. H2S04 is deep inky blue. Alcoholic KOH forms, with difficulty, a blue solution. Soluble form. — Soluble in the above liquids. Its solution in boiling glacial acetic acid is violet when hot, blue when cold. Solution in cone. H2S04 is clear indigo-blue. Alcoholic potash forms a violet solution. Di-sulphonic aci d. — From (/3) -naphthol- sulphonic acid and diazotised NH2.C6H4.N2.C10H6.NH2. (a)-Oxy-naphthalene-p-azo -benzene - (a) -azo- naphth.alene-azo-(a)-naph.thol. Similar to the preceding. Bronzy powder, forming a blue solu- tion in alcoholic KOH, and an indigo-blue solu- tion with cone. HSO." (£)-Oxy-naphth.alene - p - azo - benzene-azo- m~ xylene-azo-(0)-napb.thol HO.CIOH.— N,— C.H.— N,— C.H^£e.,— N,— C,0H.on. From NH2.C6H4.N2.C6H2Me2NH2 by diazotising and adding sodium (0)-naphthol (Meldola, C. <7. 43, 439). Small green needles (from xylene). Its solution in aniline is reddish-violet; in xylene, violet ; in hot alcoholic KOH, bluish- violet ; in cone. H2SO4 greenish-blue, becoming blue on dilution. It is insoluble in alcohol and in glacial acetic acid. Its sulphonic acid dyes silk and wool dull violet. Tri-oxy-tri-naphthalene-hexa-azo-tri-phenyl- carbinol HO.C(C6H4— N2— CIOHSOH)3*. From diazotised para -rosani line and (a)- or ()B)- naph- thol in alkaline solution (Meldola, C. J. 47, 668). Orange amorphous powders. Similar compounds may be got from ordinary rosaniline. They dye silk and wool orange. AZO- COT I ON DYES. The azo- dye-stuff 3 obtained from benzidine and its homologuea (Congo-red, benzopurpurine, deltapurpurine, benzaurine, chrysamine, benzazurine, &c.) have the special characteristic of dyeing cotton with- out a mordant. This property depends upon the constitution of the diphenyl molecule, for benzidine itself (and other diphenyl bases) readily combines with the cotton fibre. This is easily shown by allowing cotton to soak for 24 hours in a cold solution of benzidine hydro- chloride, wringing, drying at the ordinary tem- perature, and washing thoroughly with hot and cold water ; if the cotton thus mordanted with benzidine is now passed through a dilute solu- tion of nitrous acid, and finally treated with a solution of (o)-naphthylamine-sulphonic acid it becomes dyed with Congo-red (Mohlau, B. 19, 2014). Tetrazo-diphenyl (diazotised benzidine) forms red dye-stuffs by combination with (a), and (/5)-mono-sulphonic acids of (0)-naphthol or with the G di-sulphonic acid. The B di- sulphonic acid (Na salt insoluble in spirit) however exhibits a very peculiar reaction. One mol. of tetrazo-diphenyl combines with one mol. of the R di-sulphonate forming a dye-stuff which is red. If two mols. of the sulphonate are taken one mol. remains in solution unused. If now tho ppd. red colouring matter is heated with the mother liquor, the second mol. of di-sulphonate is taken up and a blue colouring matter is pro- duced. A similar reaction has been observed with many other di-amido- bodies (Schultz, B. 17, 461). In general, the tetrazo- derivatives of diphe- nyl, ditolyl, <fec. (obtained by diazotising benz- idine and its homologues) can combine with either one or two mols. of a phenol, amine, or their sulphonic and carboxylic acids. The compounds with one mol., viz., ^"^jj2 j»' » ^o tolerably stable, and sparingly soluble; by boiling with water or with alcohol the uncom- bined diazo- group is replaced by OH or by hydrogen. These half -conjugated diazo- com- pounds readily combine with a second mol. of phenol or amine, so that mixed azo- compounds can be thus obtained. The latter bodies are colouring-matters of various shades, and dye cotton direct without a mordant (Lange, JB. 19, 1637 ; Marlius, B. 19, 1755). AZOXLMS 423 The azo- compounds (Hessian yellow, Hessian purple, curcumine, &c.) obtained by combining two mols. of a phenol, amine or respective sulphonio acid, or one mol. of one amine or phenol and one mol. of another, with the tetrazo- compound derived from di-p-amido-di-phenyl- ethyleneor its sulphonic acids, have the property of dyeing unmordanted cotton from a soap-bath. The compound from (o)-naphthol-sulphonic acid dyes cotton a bluish -violet, (£)-naphthol-R-di- sulphonic acid a blue, (a)-naphthylamine-sul- phonic acid a red salicylic acid a yellow, &c. (Bender a. Schultz, B. 19, 3234). The di-amido- derivatives of fluorene also give colouring matters which dye cotton. To the class of cotton colours also belongs the compound which has recently been introduced under the name of 'Primuline.' This body dyes unmordanted cotton from an alkaline bath a greenish yellow. It is an amido- compound and may be diazo- tised upon the fibre. By treatment of the cotton thus prepared with solutions of amines or phenols, fast colours (red, orange, and brown) may be produced (Green, priv. com.). TEIAZOL. A name given to the hypo- HN - N I II thetical C2H3Ng or HC CH (Bladin, B. 19, 2598) (v. PHENYL-METHYL-TBIAZOL and CYANO-PHENYL METHYL-TRIAZOL). AZO -MECuNIC- ACETIC ACID v. Dioxy- carboxy - methyl-phthalide - izo-dioxy -phthalide- acetic acid. AZO-DI-METHYL-BTYDROQTJINONE v. Di- oxy-benzene-kzo-hydn quinone. AZO-NAPHTHALENE v. Naphttialene-tao- naphthalene. TETRAZONES. Compounds of the form R2:N.N:N.N:R2 obtained by oxidising unsym- metrical di-alkylated hydrazines (q. v.). AZONIUM BASES. Compounds of the form NH2.NRR'R"(OH) (Fischer). The name has been also applied by Witt (B. 20, 1183) to compounds of the form X' AZO-OPIANIC ACID is amido-hemipic anhy- dride, v. HEMIPIC ACID. AZOPHENINE CS6H29N5. [237°]. Is formed by the action of a variety of azo- and nitroso- compounds (e.g. benzene-azo-aniline, toluene- azo-toluidine, phcnyl-amido-benzene-azo-benz- ene, chrysoidine, diphenyl-nitrosamine, nitroso- di-methyl-aniline, &c.) upon aniline (Kimich, B. 