2,3-Diaminotoluene → 1,1-Diphenylethane

Participants

Reaction Steps

3(a) An aromatic polyamine mixture made up of 2.6% of diaminotoluene (isomer mixture), 6.2% of diaminomethyl diphenylmethane (isomer mixture containing more than 90% of diamines of the type containing one amino substituent on each aromatic ring) and 91.2% of triamino-methyl diphenyl methane (isomer mixture containing more than 90% of triamines with one amino group on the unsubstituted aromatic ring and two amino groups on the methyl-substitued aromatic ring) was obtained by the nitration of methyl diphenyl methane, followed by catalytic hydrogenation using Raney nickel in accordance with European Patent Application No. 46,917. 350 g of this polyamine mixture were hydrogenated at 200° C./275 bars in accordance with Example 1(a) in the presence of 35 g of ruthenium (5%)/aluminum oxide supported catalyst and 35 g of ammonia in a 0.7 liter stirrer-equipped autoclave. After distillation twice, the hydrogenation product which was 91% triaminomethyl dicyclohexyl methane corresponding to formula (I) (R=CH3), and 9% diaminomethyl dicyclohexyl methane, was isolated in a yield of 69.2 g (B.p. 132°-148° C./0.1 mbar).

Provenance & Evidence