The main goals of this research proposal are (1) the mechanistic analysis of a novel aluminum salen catalyzed asymmetric conjugate addition reaction, (2) expansion of substrate scope and utility of the reaction, (3) development of a general synthetic approach for the important class of pentem antibiotics, and (4) the rational development and screening of new conjugate addition reactions. Considering the plethora of potentially valuable compounds resulting from asymmetric conjugate addition reactions, the attainment of these research objectives is deemed a worthwhile achievement.