Diaminobenzophenone hydrochloride

A mixture of 9.6 parts of 4-amino-3-nitrobenzophenone, 160 parts of methanol, 8 parts of concentrated hydrochloric acid and 1 part of palladium-on-charcoal catalyst 10% is hydrogenated at normal pressure and at room temperature. After the calculated amount of hydrogen is taken up, hydrogenation is stopped. The catalyst is filtered off and the solvent is evaporated. The solid residue is triturated in 2-propanol. The latter is partly evaporated and the solid product is filtered off, washed with 2-propanol and dried, yielding 3,4-diaminobenzophenone hydrochloride MP 207 C. 

By heating together 4-ehloro-3-nitro benzophenone and ammonia at 125°C for 24 hours in the presence of sulfolane yields 4-amino-3-nitrobenzophenone. The resulting product on being treated with hydrochloric acid and hydrogenation with Pd-on-charcoal as a catalyst yields diaminobenzophenone hydrochloride. This on being treated with S-methyl thiourea in the presence of methyl chloroformate... 

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