A short, stereoselective synthesis of (3R,4R)-4-acetoxy-3-[(R)-1′((t-butyldimethylsilyl)oxy) ethyl]-2-azetidinone, key intermediate for the preparation of carbapenem antibiotics

A short stereoselective synthesis of the acetoxy azetidinone (1), an important precursor of several biologically active β-lactam antibiotics, has been accomplished in seven steps and 32.8% overall yield from the easily available and inexpensive (R) ethyl 3-hydroxybutanoate. Chirality 10:91–94, 1998. © 1997 Wiley-Liss, Inc.