It may also be obtained by oxidizing the symmetrical trinitrobenzene with potassium ferricyanide in alkaline solution (P. Hepp, Ann.
Trinitrobenzenes, C 6 H 3(N02)3.-Asymmetrical (1.2.4) trinitrobenzene results from the action of fuming nitric and sulphuric acids on para-dinitrobenzene.
Symmetrical (1.3.5) trinitrobenzene is formed by the further nitration of meta-dinitrobenzene with fuming sulphuric and nitric acids; by the action of hydrochloric acid on sodium malonyl aldehyde (H.
This holds for benzene and phenol, and is supported by the observations of Gossner on [1.3.5] trinitrobenzene and picric acid (1.3.5-trinitro, 2 oxybenzene); these last two substances assume rhombic forms, and picric acid differs from trinitrobenzene in having w considerably greater, with x and slightly less.
Torray's observations on nitromalonic aldehyde, N02 CH(CHO)2,formed by acting on mucobromic acid, probably CHO CBr:CBr:000H, with alkaline nitrites; this substance condenses with acetone to give p-nitrophenol, and forms [I.3.5]-trinitrobenzene when its sodium salt is decomposed with an acid.