Reactions of metallocarbenes derived from N-sulfonyl-1,2,3-triazoles
Metal-stabilized carbenes derived from diazo compounds have become broadly useful reactive intermediates for organic synthesis. This tutorial review will describe the recent advances in using N-sulfonyl-1,2,3-triazoles as precursors for the formation of metal-bound imino carbene intermediates. These intermediates undergo a variety of synthetically useful transformations, which include transannulation reactions to generate new heterocycles, cyclopropanation and subsequent ring expansions, ylide formation with subsequent rearrangements, and C–H functionalization. Furthermore, many of these transformations can be conducted with high levels of enantioselectivity by use of chiral rhodium(II) catalysts.