Jb. Deeter et al., STEREOSELECTIVE SYNTHESIS OF CIS-SUBSTITUTED AZETIDINONES FROM PENICILLIN - A FORMAL TOTAL SYNTHESIS OF LORACARBEF, Tetrahedron letters, 34(19), 1993, pp. 3051-3054
A new method for the synthesis of chiral azetidinones bearing a carbon
-carbon bond at the 4-position is described. The preparation involves
a stereoselective alkylation-reduction of a silylated 4-phenylsulfonyl
azetidinone. The utility of this method was demonstrated by a formal
total synthesis of loracarbef.