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

Abstract

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 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)]. QTAIM analysis of the Cu-H-BEt3 interaction indicates a hydride complex stabilized by the Lewis acid BEt3.

Distinct Reactivity Modes of a Copper Hydride Enabled by an Intramolecular Lewis Acid

“…These data suggest that 3 is best described as a borohydride anion interacting with copper, with some copper hydride resonance contribution. This depiction has also been invoked in related compounds, , and we note that similar (NHC)­CuH–BR 3 complexes can be induced to exhibit a Cu–hydride-type reactivity (carbonyl hydrosilylation) in select organometallic transformations . Importantly, our analysis of 3 suggests that the Cu–H–BR 3 moiety contains both Cu–H character and B–H character.…”

Catalytic potential of silicon nanocages for CO2 reduction reaction to CO, CH4, HCOOH, HCHO and CH3OH production

“…The calculated adsorption energies (∆E adsorption ) of CO 2 and other possible intermediates of processes of CO 2 reduction reactions on surfaces of Ni-C 50 and Ni-Si 50 nanocages are calculated [28][29][30] as following: (1) where the E nanocage are total energies of Ni-C 50 and Ni-Si 50 nanocages and E specie are total energies of possible intermediates of processes of CO 2 reduction reactions and the E specie−nanocage are total energies of complexes of Ni-C 50 and Ni-Si 50 nanocages with intermediates of processes of CO 2 reduction reactions [31][32][33]. The changing of Gibbs free energy (∆G reaction ) of reaction steps of possible mechanisms for CO 2 reduction reactions on surfaces of Ni-C 50 and Ni-Si 50 nanocages are calculated [34][35][36][37] as following:…”

1H NMR global diatropicity in copper hydride complexes

“…Since the discovery of Stryker's reagent, [HCu-PPh 3 ] 6 , 1 now widely employed to regioselectively hydrogenate αβ-unsaturated carbonyl compounds, several copper hydrides complexes have been synthesized. 2–28 The broad variety of applications for these complexes include 23,24,29–31 hydrogen storage, 5,32–36 catalysis, 28,32,37–45 energy storage, 38,32 and energy conversion, 32,46 to give but a few examples. Within this family of compounds, several coordination modes have been observed for Cu–H hydrides such as adopting a bridge position, face-capping or interstitial positions to help to stabilize the cluster.…”