Tetrahedron

Highly stereocontrolled synthesis of the 1β-methylcarbapenem key intermediate by the reformatsky reaction of 3-(2-bromopropionyl)-2-oxazolidone derivatives with a …

Y Ito, A Sasaki, K Tamoto, M Sunagawa, S Terashima

Index: Ito; Sasaki; Tamoto; Sunagawa; Terashima Tetrahedron, 1991 ,  vol. 47,  # 16-17  p. 2801 - 2820

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Citation Number: 48

Abstract

The key synthetic intermediate (4) of 1β-methylcarbapenems (1–3) was efficiently synthesized by employing highly stereocontrolled Reformatsky reaction (C4-alkylation) of 3- (2-bromopropionyl)-2-oxazolidone derivatives (6) with (3R, 4R)-4-acetoxy-3-[(R)-1-(t- butyldimethylsilyloxy) ethylJ-2-azetidinone (5) in the presence of zinc dust followed by removal of 2-oxazolidone moieties. The best diastereoselectivity (β: α= 95: 5) could be ...