Recent Advances in Enantioselective Photochemical Reactions of Stabilized Diazo Compounds

Diazo compounds have proven to be a useful class of carbenes or metal carbenoids sources under thermal, photochemical, or metal-catalyzed conditions, which can subsequently undergo a wide range of synthetically important transformations. Recently, asymmetric photocatalysis has provoked increasing research interests, and great advances have been made in this discipline towards the synthesis of optically enriched compounds. In this context, the past two decades have been the most productive period in the developments of enantioselective photochemical reactions of diazo compounds due to a better understanding of the reactivities of diazo compounds and the emergence of new catalytic modes, as well as easier access to and treatment of stabilized diazo compounds. This review highlights these impressive achievements according to the reaction type, and the general mechanisms and stereochemical inductions are briefly discussed as well.

Sulfoxonium Ylide Derived Metal Carbenoids in Organic Synthesis

As pioneered by Corey and Chaykovsky, sulfoxonium ylides have had widespread application in organic synthesis for more than a half century. In most of the reactions, sulfoxonium ylides were used to react with electrophiles. Under suitable reaction conditions these ylides can generate metal carbenoids and react with nucleophiles. By combining the typical reactivity of sulfoxonium ylides with transition-metal catalysis, a growing number of investigations have expanded their application in organic synthesis. This review provides an update on the preparation of sulfoxonium ylides and their applications in carbenoid transfer reactions.1 Introduction2 Preparation of Sulfoxonium Ylides3 Investigation for Carbenoid Formation from Sulfoxonium Ylide 4 X–H (X = N, O, S, C) Functionalization Reactions5 Polymerizaton of Carbenoids Generated from Sulfoxonium Ylides6 Conclusion and Perspective