Dicyclohexylcarbodiimide → 5-benzyl-3-furyl-methyl (1R,trans) 2,2-dimethyl-3-(1,2-propadienyl)-cyclopropane-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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 1.23 g of 5-benzyl-3-furyl-methanol in 7 ml of methylene chloride was added to the mixture which was stirred at 20° C. for 24 hours and was filtered. The filtrate was evaporated to dryness under reduced pressure and the residue was chromatographed over silica gel. Elution with a 3-7 petroleum ether (b.p.=35° to 70° C.)-benzene mixture and then a 7-3 petroleum ether (b.p.=35° to 70° C.)-benzene mixture yielded 825 mg of 5-benzyl-3-furyl-methyl (1R,trans) 2,2-dimethyl-3-(1,2-propadienyl)-cyclopropane-carboxylate with a specific rotation of [α]D20 =-24° (c= 0.6% in chloroform).

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