Sodium Carbonate → (1R,5R)-2,2,2-trichloroethyl-5-hydroxy-2-cyclopentene-1-carbamate

Participants

Reaction Steps

A 10.18 (103 mM) quantity of crude (3R,4R)-3-amino-4-hydroxycyclopentene (prepared as in Preparation 19, step 4) is dissolved in 75 ml of water and the mixture treated with 10.6 g (100 mM) of sodium carbonate. The mixture is then cooled in an ice bath to <10° and treated dropwise while stirring vigorously, with 24 g (110 mM) of trichloroethylchloroformate over 30 minutes. After 3 hours the reaction is filtered and the collected solid product washed throughly with water. On drying there is obtained 22.43 g of (1R, 5R)-2,2,2-trichloroethyl-5-hydroxy-2-cyclopentene-1-carbamate as crystalline solid, m.p. 82°-84°. Recrystallization of a small sample from isopropylether-Skellysolve B gives material with a m.p. 87°-87.5° [α]-92° (C=0.14, MeOH).

Provenance & Evidence