1,4-Carbazolchinone ausp-Benzochinon und primären aliphatischen Aminen. Das vermeintliche und das wahre 2-Methylamino-benzochinon

The compound which is obtained in the reaction of 1,4-benzoquinone with methylamine in chloroform was supposed to be 2-methylaminobenzoquinone; actually it is 6-hydroxy-9-methyl-3-methylamino-1,4-carbazolquinone. The structure is proved by spectroscopic methods, through derivates, zinc dust distillation and via synthesis from 2,5,2,5-biphenyl-diquinone. A second main product, 2,5-bis(methylamino)quinone, is obtained; varying the reaction conditions shows especially the influence of the solvent. One of the intermediate products is the true 2-methylamino-1,4-quinone. Other substituted 9-alkyl-3-alkylamino-6-hydroxy-1,4-carbazolquinones can be prepared by reaction with the corresponding primary amines.