Dicyclohexylcarbodiimide → HCID 13647094, compound

Participants

Reaction Steps

A solution of 6.65 g. of Nα -benzyloxycarbonyl-D-phenylalanine (0.022 mol) and 4.38 g. (0.022 mol) of L-leucine methyl ester hydrochloride in 60 ml. of spectrograde dimethylformamide is chilled in ice and treated with 3.0 ml. of triethylamine (2.24 g.). 1-Hydroxybenztriazole, 3.3 g., and dicyclohexylcarbodiimide, 5 g., are added and the reaction stirred to room temperature overnight and for 24 hours at room temperature. The mixture is filtered and the solvent evaporated under reduced pressure. The residue is dissolved in 200 ml. of ethyl acetate and washed with 0.1N hydrochloric acid, saturated salt solution, 5% sodium bicarbonate solution, saturated salt solution and water. The ethyl acetate solution is dried over magnesium sulfate, filtered and evaporated to a crystalline residue. The product is recrystallized twice from ethyl acetate and petroleum ether; 7.3 g.; m.p. 125°-126° C.; [α]D23 -20.3° (c 1.02, methanol).

Provenance & Evidence