December 2024

In recent years, rhodium catalysis has evolved as a powerful tool for chemo- and stereocontrolled syntheses of chiral molecules through C–H functionalization. In particular, chiral cyclopentadienyl rhodium (CpRh) complex-catalyzed asymmetric C–H functionalization reactions have gained ever-increasing attention in organic synthesis. However, the design and synthesis of novel chiral Cp ligands remain challenging due to the difficulty of imparting chiral elements into the Cp moiety. In this account, we introduce our research progress in the syntheses of chiral cyclopentadienyl ligands and their applications in rhodium-catalyzed asymmetric C–H functionalization reactions.1 Introduction2 SCpRh-Catalyzed Enantioselective C–H Functionalization Reactions3 CpmRh-Catalyzed Enantioselective C–H Functionalization Reactions4 BOCpRh-Catalyzed Enantioselective C–H Functionalization Reactions5 BCSCpRh-Catalyzed Enantioselective C–H Functionalization Reactions6 Conclusion

A simple and efficient one-pot protocol has been developed for the synthesis of 1H-tetrazole and 1-methyltetrazole derivatives from aldehydes under mild and metal-free conditions using ammonium azide or methyl azide, respectively. A number of tetrazole derivatives were obtained in moderate to high yields (75–92%) in green solvents at a moderate temperature. These reactions presumably proceed through the formation of a nitrile in situ. The mild conditions and the easy workup and purification make this method highly valuable.