Ortho-para-isomerism in the preparataion of diaminodiphenylmethane / by Harold King.

  • King, Harold
Date:
1920.]
Catalogue details

Licence: Public Domain Mark

Credit: Ortho-para-isomerism in the preparataion of diaminodiphenylmethane / by Harold King. Source: Wellcome Collection.

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    CIX.—'Ortho-para-isomei'ism in the Preparation of Diaminodiphenylmethane. By Harold King. In the course of an investigation of the nitro-derivatives of diaminodiphenylmethane, prepared either from dianilinomethane or from anhydroformaldehydeaniline and aniline, it was found that the crude, distilled diaminodiphenylmethane was a mixture of the 4:4;- and 2 :4/-derivatives in the proportion of about 9 to 1. By crystallising the nitration products, 2 : 2/-dinitro-4 :4/-diamino- diphenylmethane was first isolated, and from the mother liquors a mononitro-derivative, which, on removal of the amino-groups, subsequent reduction, and acetylation, gave 4-acetylamin odiphenyl- methane. The mononitro-derivative must have arisen from 2 :4/-diaminodiphenylmethane present in the starting material, as was confirmed by the separation of the two isomeric bases and the mono-nitration of the unsymmetrical base. Experimental. Preparation of Diaminodiphenylmethane. From Dianilinom ethane.—Fifty grams of crystalline dianilino- methane were digested with 59 c.c. of aniline, 31 c.c. of concen¬ trated hydrochloric acid, and 24 c.c. of water for twelve hours at 95°. The product was made alkaline and completely freed from aniline by steam distillation. The residual non-volatile base, after washing by agitating with fresh quantities of water, was distilled