Visible Light-Promoted Transformation of Diazo Compounds via the Formation of Free Carbene as Key Intermediate

Carbene is one of the most important synthetic intermediates in organic synthesis.In the past few decades, transition-metal catalyzed carbene transfer reactions have made remarkable development.Recently, visible light-promoted transformation of diazo compounds through the formation of free carbene as key intermediate begun to rise.The reaction only need visible light as the sole energy source which meets the concept of green chemistry.Since the pioneering works developed by the groups of Diaves and Zhou, photo-promoted transformation of diazo compounds has attracted more and more attentions.On the basis of previous work, the latest progress in this field is further improved, which mainly focuses on the recent new transformation reactions of diazo compounds under visible light irradiation and the contributions reported from Chinese research group.The future development direction, as well as challenges in this field is prospected.