Dicyclohexylcarbodiimide → (S)alpha-cyano-3-phenoxy-benzyl (1R,trans) 2,2-dimethyl-3-(1,2-propadienyl)-cyclopropane-carboxylate

Participants

Reaction Conditions

Reaction Steps

1.22 g of dicyclohexylcarbodiimide and a few crystals of 4-dimethylamino-pyridine were added at 0° C. to a solution of 900 mg of (1R,trans) 2,2-dimethyl-3-(1,2-propadienyl)cyclopropane-carboxylic acid in 20 ml of methylene chloride and the mixture was stirred at 0° C. for 15 minutes. A solution of 1.46 g of (S)α-cyano-3-phenoxy-benzyl alcohol in 7 ml of methylene chloride was added to the mixture which was stirred for 5 hours at 20° C. and then filtered. The filtrate was evaporated to dryness under reduced pressure and the residue was chromatographed over silica gel. Elution with a 6-4 and then a 7-3 benzene-petroleum ether (b.p.=35° to 70° C.) mixture yielded 754 mg of (S)α-cyano-3-phenoxy-benzyl (1R,trans) 2,2-dimethyl-3-(1,2-propadienyl)-cyclopropane-carboxylate with a specific rotation of [α]D20 =-25° (c=0.7% in chloroform).

Provenance & Evidence