Dicyclohexylcarbodiimide → 2,5-Dimethylcyclopentyl N-t-butoxycarbonyl-1-aminocyclopropanecarboxylate

Beteiligte Stoffe

Reaktionsschritte

To a solution of 2,5-dimethylcyclopentanol (0.55 g), compound 1 (0.97 g), and 4-(dimethylamino)pyridine (0.06 g) in methylene chloride (100 ml) was added dicyclohexylcarbodiimide (1.09 g), and the resulting mixture was stirred overnight. The precipitated dicyclohexylurea was removed by filtration, and the filtrate was evaporated. Ethyl acetate was then added to the residue, and the mixture was filtered again. The filtrate was washed with 1M hydrochloric acid, saturated aqueous sodium bicarbonate, and water, dried over magnesium sulfate, and the solvent was evaporated to a colorless oil (1.18 g. 83%). The product was purified by column chromotography on silica gel, 4:1 hexane:ethyl acetate, eluent. NMR (CDCl3): δ0.92 (t, 6H, 2CH3), 1.05-2.10 (m, 10H, cyclopentyl, cyclopropyl), 1.40 (s, 9H, t-Bu), 4.60 (dd., 1H, CO2CH), 5.05 (br. s, 1H, NH).

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