Stereocontrolled Aldol-Like Reactions Involving Oxocarbenium Intermediates

Abstract Oxocarbenium cations are key intermediates for the stereocontrolled construction of carbon–carbon bonds. In particular, we have developed a wide range of stereoselective aldol-like processes that take advantage of the high reactivity of the oxocarbenium species arising from acetals, glycals, and orthoesters with metal enolates. This Account describes the development and optimization of such processes, together with other significant contributions, with a particular emphasis on their application to the synthesis of natural products. 1 Introduction 2 Substrate-Controlled Processes 2.1 Additions to Acyclic Acetals 2.2 Additions to Cyclic Acetals 3 Chiral-Auxiliary-Based Processes 3.1 Additions to Acyclic Acetals 3.2 Additions to Cyclic Acetals and Glycals 4 Chiral-Catalysis-Based Processes 4.1 Organocatalysis 4.2 Metal Catalysis 5 Conclusions