M. Altamura et E. Perrotta, 2-(IODOMETHYL)PENEMS AS USEFUL SUBSTRATES IN THE WITTIG OLEFINATION -SYNTHESIS OF 2-ARYLETHENYL PENEMS, Tetrahedron letters, 35(9), 1994, pp. 1417-1420
Wittig olefination at room temperature on the new (2-iodomethyl) penem
s 4 gave a series of (2-arylethenyl) penems 5 with different E/Z selec
tivity depending on the position and electron effect of the substituen
t on the aryl aldehyde.