Recent progress on donor and donordonor carbenes

Donor and donordonor carbenes are two important kinds of carbenes, which have experienced tremendous growth in the past two decades. This review provides a comprehensive overview of the recent development of donor and donordonor carbene chemistry. The development of this chemistry offers efficient protocols to construct a wide variety of CC and CX bonds in organic synthesis. This review is organized based on the different types of carbene precursors, including diazo compounds, hydrazones, enynones, cycloheptatrienes and cyclopropenes. The typical transformations, the reaction mechanisms, as well as their subsequent applications in the synthesis of complex natural products and bioactive molecules are discussed. Due to the rapidly increasing interest in this area, we believe that this review will provide a timely and comprehensive discussion of recent progress in donor and donordonor carbene chemistry. This review highlights the recent advances in donor and donordonor carbenes.