Copper–Ligand Cooperativity in H2 Activation Enables the Synthesis of Copper Hydride Complexes

• Published in: Organometallics 2021-07, Vol.40 (13), p.2064-2069
• Main Authors: Aloisi, Alicia, Crochet, Étienne, Nicolas, Emmanuel, Berthet, Jean-Claude, Lescot, Camille, Thuéry, Pierre, Cantat, Thibault
• Format: Article
• Language: English
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/acs.organomet.1c00212

Copper­(I) complexes of a new participative triphosphane ligand (2 H ) have been prepared and structurally characterized: in particular, [Cu­(2 H )­I] and [Cu­(2)]2. Hydrogenation of the latter species afforded the trimetallic hydride species [Cu3(2)2(μ-H)] or, in the presence of BEt3, [Cu­(2 H )­(HBEt3)]. Their formation evidences the transient formation of [Cu­(2 H )­H] formed by hydrogenolysis of the Cu–N bond of [Cu­(2)]2. [Cu­(2 H )­(HBEt3)] behaves like a hydride complex and inserts CO2 to yield the formate product [Cu­(2 H )­(O2CH)]. A QTAIM (quantum theory of atoms in molecules) analysis of the Cu–H–BEt3 interaction indicates a hydride complex stabilized by the Lewis acid BEt3.