[Rh2(phesp)2]: a Bulkier [Rh2(esp)2] Analog to Tune the Site‐Selectivity in Carbene C–H Insertion Reactions

Abstract

[Rh2(phesp)2], a new dirhodium(II) complex bearing a bulky bidentate bis‐carboxylate ligand, has been prepared in two steps from commercially available compounds. Its X‐ray structure revealed distinctive features with a strong distortion around the dirhodium(II) core, illustrated by important torsion angles of up to 9.0°. It has been evaluated as catalyst as a bulky version of the prominent [Rh2(esp)2] complex in carbene C–H insertion reactions. [Rh2(phesp)2] proved as active as [Rh2(esp)2], and showed an intermediate selectivity between [Rh2(esp)2] and bulky [Rh2(tpa)4] in both intra‐ and intermolecular reactions with donor‐acceptor and acceptor‐acceptor diazo compounds, comprising challenging C(sp3)–H insertion into pentane.