Dicyclohexylcarbodiimide → (1-propargyl-2,4-dioxo-imidazolidin-3-yl)-methyl(1R,trans)2,2-dimethyl-3-(cyclobutylidenemethyl)-cyclopropane-1-carboxylate

Participants

Reaction Steps

A solution of 3.6 g of (1-propargyl-2,4-dioxo-imidazolidin-3-yl)-methanol in 10 ml of methylene chloride was added at 20° C. to a mixture of 4 g of (1R,trans)2,2-dimethyl-3-(cyclobutylidenemethyl)-cyclopropane-1-carboxylic acid, 4.6 g of dicyclohexylcarbodiimide, 20 ml of methylene chloride and a catalytic amount of 4-dimethylamino-pyridine and the mixture was stirred at 20° C. for 17 hours and was vacuum filtered. The filtrate was evaporated to dryness under reduced pressure and the residue was chromatographed over silica gel. Elution with a 7-3 cyclohexane-ethyl actate mixture and then a 95-5 benzene-ethyl acetate mixture yielded 1.2 g of (1-propargyl-2,4-dioxo-imidazolidin-3-yl)-methyl(1R,trans)2,2-dimethyl-3-(cyclobutylidenemethyl)-cyclopropane-1-carboxylate.

Provenance & Evidence