4 2 39 dinitro isomer and less than 1 of the 4 3 39 isomer was dissolved in toluene 30 ml to this solution was added 4 nitrophenol 2 0 g the hot solution was analyzed by gas liquid chromatography and contained 82 42 dinitrodiphenyl carbonate 99 86 of 4 4 39 dinitro isomer 0 14 of 4 2 39 dinitro isomer the balance of the material is nitrophenols the hot solution was chilled overnight and the resulting solid collected by filtration dried and weighed the resulting material 15 44 g was analyzed by glc and found to contain the desired carbonate isomer 90 4 of 4 4 39 dinitro isomer trace of 4 2 39 dinitro isomer and nitrophenols 7 49 of the 4 isomer and 2 11 of 2 isomer diphenyl carbonate 107 2 g 0 5 mol was nitrated with a mixture of nitric and sulfuric acids ethyl acetate was added to the reaction mixture after the reaction had been quenched with ice the organic layer was dried and 4 nitrophenol 10 0 g was added to the solution this solution was concentrated and the resulting solid dried in a vacuum oven 80 u00b0 c overnight the resulting crude product was washed with hexane and dried again resulting in crude dinitrodiphenyl carbonate 179 5 g containing isomeric carbonates in the ratio 93 4 6 6 4 4 39 dinitro isomer to 4 2 39 dinitro isomer this crude mixture of carbonates was taken up in toluene 400 ml and 4 nitrophenol 5 0 g was added hexane 150 ml was added and the solution allowed to cool and crystallize the resulting solid was dried and analyzed by glc the results of this analysis indicated that the.