An Update on the Synthesis of β-Lactams
Pp. 296-354 (59)
M. Teresa Aranda, Paula Pérez-Faginas and Rosario González-Muñiz
As a consequence of the renewed interest of β–lactams in organic and
medicinal chemistry, research in this field is constantly providing new appealing
advances. This chapter focuses on synthetic aspects related to the generation of this
four-membered heterocyclic ring, published since 2000, with special emphasis on
stereoselective synthetic approaches. The compendium deals with methods for
achieving diastereo- and enantioselectivity during [2+2] cycloadditions, with the
Staudinger reaction still as first choice, but also important achievements have been
published for the imine-enolate condensation, the carbonylative cycloaddition and the
Kinugasa reaction. Significant success has also been accomplished in the synthesis of
innovative 2-azetidinones through the formation of a single bond. In this respect, the
C3-C4 bond formation, through intramolecular cyclization of linear epoxy or halo
derivatives and the carbenoid C-H insertion are among the most effectively exploited
procedures. In addition, adaptation of most procedures to solid-phase methodologies has
facilitated the generation of molecular diversity based on the β–lactam skeleton.
β–lactams, 2-azetidinones, stereoselective synthesis, chiral
auxiliaries, chiral catalysts, memory of chirality.
Instituto de Química Médica, CSIC, Juan de la Cierva 3, 28006 Madrid, Spain.