heterocyclic ring of the formula str3 wherein r 5 is hydrogen lower alkyl or lower alkoxy and pharmaceutically acceptable acid addition salts thereof are disclosed these compounds and their salts possess central nervous system activity and are useful as anti anxiety agents application_number US 78161977 A description the term 34 lower alkyl 34 as used throughout this specification is meant to include straight or branched chain hydrocarbon groups having from 1 to 4 carbon atoms i e methyl ethyl n propyl i propyl n butyl i butyl and t butyl similarly the term 34 lower alkoxy 34 is meant to include such alkyl groups linked to an oxygen atom i e methoxy ethoxy t butoxy etc preferred embodiments of this invention are the compounds of formulas i and ii wherein r 1 is lower alkyl of 1 to 4 carbons especially ethyl r is str7 n is 3 r 3 and r 4 are the same and are methyl or ethyl especially methyl the new compounds of formula i can be prepared by several methods the preferred methods involve reacting a ketone of the formula str8 with a grignard reagent of the formula str9 wherein hal is cl or br and n r 1 r 2 r 3 and r 4 are as defined above this reaction is carried out in an inert solvent such as diethylether dibutylether or tetrahydrofuran by heating at about the reflux temperature for several hours alternatively certain compounds of formula i wherein n is three can also be prepared by reacting the ketone of formula ii with an alkyl magnesium halide grignard reactant of the formula to yield the compound of the formula str10 amination of the olefinic linkage of the compound of formula vii by reacting with an amine str11 yields the compound.