Hydride Transfer to Gold: Yes or No? Exploring the Unexpected Versatility of Au⋅⋅⋅H−M Bonding in Heterobimetallic Dihydrides

摘要: The potential for coordination and H-transfer from Cp2 MH2 (M=Zr, W) to gold(I) gold(III) complexes was explored in a combined experimental computational study. [(L)Au]+ cations react with WH2 giving [(L)Au(κ2 -H2 WCp2 )]+ (L=IPr (1), cyclic (alkyl)(amino)carbene (2), PPh3 (3) Dalphos-Me (4) [IPr=1,3-bis(diisopropylphenyl)imidazolylidene; Dalphos-Me=di(1-adamantyl)-2-(dimethylamino)phenyl-phosphine], while [Au(DMAP)2 ]+ (DMAP=p-dimethylaminopyridine) affords the C2 -symmetric [Au(κ-H2 )2 (5). Dalphos complex 4 can be protonated give bicationic adduct H, showing AuI ⋅⋅⋅H+ -N hydrogen bonding. Lewis acid [(C^N-CH)Au(C6 F5 )(OEt2 binds an Au-H-W σ-complex. By contrast, pincer species [(C^N^C)Au]+ adds by purely dative W→Au bond, without Au⋅⋅⋅H interaction. biphenylyl-based chelate [(C^C)Au]+ forms [(C^C)Au(μ-H)2 , two 2-electron-3-centre W-H⋅⋅⋅Au interactions practically no Au-W donor acceptor contribution. In all these complexes, strong but polarized W-H bonds are maintained, gold. On other hand, reactions of ZrH2 gold led cases rapid formation hydrides. Relativistic DFT calculations were used rationalize striking reactivity bonding differences heterobimetallic hydride along analysis their characteristic NMR parameters UV/Vis absorption properties.