Transition Metal Catalyzed Insertion Reactions with Donor/Donor Carbenes

• Published in: Angewandte Chemie International Edition 2021-03, Vol.60 (13), p.6864-6878
• Main Authors: Bergstrom, Benjamin D., Nickerson, Leslie A., Shaw, Jared T., Souza, Lucas W.
• Format: Article
• Language: English
• Subjects: Carbenes; catalysis; Catalysts; Chemical reactions; C−H insertion; donor/donor carbenes; Enantiomers; Germanium; Insertion; Metals; Selectivity; Silicon; Tin; Transition metals; X−H insertion
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202007001

Donor/donor carbenes are relatively new in the field of carbene chemistry; although applications in C−H and X−H insertion reactions are few in number, they demonstrate exquisite chemo‐ and stereo‐selectivity. Recent reports have shown that C−H, N−H, B−H, O−H, S−H, Si−H, Ge−H, Sn−H and P−H insertion reactions are feasible with a variety of transition metal catalysts, both inter‐ and intramolecularly. Furthermore, high degrees of diastereo‐ and enantioselectivity have been observed in several cases. Methods typically involve the formation of a diazo‐based carbene precursor, but procedures using diazo‐free metal carbenes have been developed with significant success. This Minireview covers transition‐metal catalyzed insertion reactions with donor/donor and donor carbenes, providing context for future developments in this emerging field. Long overlooked for having poor reactivity, metal carbenes lacking strong electron withdrawing groups can insert into the C−H bonds as well as a variety of heteroatom−H (X−H) bonds using an array of transition metals. The reduced electrophilicity results in greater functional group tolerance, new modes of stereocontrol, and new products with a range of applications.