Dichloromethane → HCID 70469043, compound

Participants

Reaction Conditions

Reaction Steps

7.51 g (0.03 mol) of (S)-1,1-dimethylethyl ester, [(2-amino-4-methylpentyl)thio]-acetic acid, 7.61 g (0.03 mol) carbobenzyloxy-L-proline, and 4.08 g (0.03 mol) 1-hydroxybenzotriazole are dissolved in 100 ml dichloromethane. The solution is cooled to 0° C. and 6.34 g (0.03 mol) of N,N-dicyclohexylcarbodiimide is added all at once. The reaction is kept at 0° C. for three days. The reaction mixture is filtered and the filtrate concentrated on a rotary evaporator. The residue is dissolved in ether, washed with 10% aqueous citric acid solution. The ether solution is dried over magnesium sulfate, filtered, and concentrated to a white solid. The solid is chromatographed on 230-400 mesh silica gel, eluting with dichloromethane followed by 3% methanol in dichloromethane. One obtains 10.99 g of [S-(R*,R*)]-phenylmethyl-2-[[[1-[[[2-(1,1-dimethylethoxy)-2-oxoethyl]thio]methyl]-3-methylbutyl]amino]carbonyl]-1-pyrrolidinecarboxylate; [α]D25 -11.6° (c 1.21, methanol).

Provenance & Evidence