Dichloromethane → HCID 54080242, compound

Participants

Reaction Steps

A solution consisting of 20.5 g (0.1 mol) of alcohol 8, 1 l of methylene chloride, and 20.5 ml of triethylamine was cooled to 0° under an argon atmosphere. Methanesulfonyl chloride (8.5 ml) was added dropwise with stirring. The resultant solution was maintained at 0° for 1/2 hr. Methanol (0.4 ml) was added, and the solvent was removed in vacuo (35°). The white solid residue was triturated with ethyl acetate and the extract filtered through a column containing silica gel (200 g). The fractions containing product (as determined by thin layer chromatography) were concentrated in vacuo yielding 2-acetamido-3-mesyloxy-4-methoxy-butenoic acid methyl ester (9) as a partially crystalline residue. Crystallization from ethyl acetate/petroleum ether (bp 35°-60°) gave one of the diastereomers as a white crystalline solid: mp 101.5°-104.5°; NMR (CDCl3) δ 6.4 (broad d, 1H, NH), 5.2 (m, 1H, CH2CH), 5.0 (m, 1H, CHNH), 3.8 (s, 3H, CH3O2C--), 3.6 (m, 2H, CH3OCH2 --), 3.3 (s, 3H, CH3OCH2 --), 3.0 (s, 3H, CH3SO 3 --), 2.0 (s, 3H, CH3CONH--). (Calcd. for C9H17NO7S: C, 38.16; H, 6.05; N, 4.94; S, 11.31. Found: C, 38.34; H, 6.21; N, 4.92; S, 11.27).

Provenance & Evidence