Methanol → HCID 86734237, compound

Participants

Reaction Steps

L-methionine in 3N NaOH is reacted with 0.5 equiv. of phosgene in toluene at about 0° with vigorous stirring. Recrystallization from 15% acetic acid of the product obtained upon acidification of the reaction mixture gives carbonyl-bis (L-methionine) in 30-40% yield, m.p. 167°-180° [α]D25 +4.8 (C, 1 methanol). The carbonyl-bis (L-methionine) is then reacted in dimethylformamide with two equiv. of dicyclohexylcarbodiimide and p-nitrophenol to yield the active ester, carbonyl-bis (L-methionine p-nitrophenyl ester) in 80% yield (after crystallization from tetrahydrofuran-ether), m.p. 183°-140°; [α]D25 = -41° (c, 0.5, dimethylformamide).

Provenance & Evidence