6-(4-Isocyanatophenoxy)-hexanoic acid methyl ester → 6-(4-{2-[4-(5-Methoxycarbonyl-pentyloxy)-phenylcarbamoyloxy]-ethoxycarbonylamino}-phenoxy)-hexanoic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To a mixture of 6-[4-(2-Hydroxyethoxycarbonylamino)phenoxy]hexanoic acid methyl ester 37 (5 g, 15.38 mmol) in toluene (50 ml) was added 6-(4-Isocyanatophenoxy)hexanoic acid methyl ester 36 (4 g, 15.2 mmol) at room temperature and heated to 60° C. for 2 hours. Toluene was distilled off and water (50 ml) was added. The solid was filtered and dried to give crude 38, which was purified by column chromatography on silica gel using chloroform as eluant to get pure 38 (8.5 g, 94%) as a white powder. M.p: 118-120.5° C.

Provenance & Evidence