Propylenediamine → N,N'-bis-(2-hydroxybenzyl)-propylenediamine

Participants

Reaction Steps

84.6 g of a bisazomethine prepared from 2 moles of salicylaldehyde and 1 mol of propylenediamine and having a melting point of 57°-58° C. are hydrogenated for 3 hours in 340 ml of isopropanol in an autoclave in the presence of 1.20 g of 5% platinum/charcoal at 45° C. and under a pressure of 50-60 atmospheres. The product crystallises out at room temperature and is dissolved by boiling, with the addition of a further 660 ml of isopropanol. The catalyst is filtered off and the diamine crystallises out on cooling. The crystals are collected by filtration, washed and dried, yielding 75.1 g of N,N'-bis-(2-hydroxybenzyl)-propylenediamine (87.5% of theory); melting point 109°-110° C.

Provenance & Evidence