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

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