Heptamethylindenyl (Ind*) enables diastereoselective benzamidation of cyclopropenes via Rh(<scp>iii</scp>)-catalyzed C–H activation

Abstract

The diastereoselective coupling of <i>O</i>-substituted arylhydroxamates and cyclopropenes mediated by Rh(iii) catalysis was successfully developed. Through ligand development, the diastereoselectivity of this reaction was improved using a heptamethylindenyl (Ind*) ligand, which has been rationalized using quantum chemical calculations. In addition, the nature of the <i>O</i>-substituted ester of benzhydroxamic acid proved important for high diastereoselectivity. This transformation tolerates a variety of benzamides and cyclopropenes that furnish cyclopropa[<i>c</i>]dihydroisoquinolones with high diastereocontrol, which could then be easily transformed into synthetically useful building blocks for pharmaceuticals and bio-active molecules.