Gold(I) Hydrides as Proton Acceptors in Dihydrogen Bond Formation. Issue 16 (6th July 2017)

• Record Type: Journal Article
• Authors: Cukrowski, Ignacy; de Lange, Jurgens H.; Groenewald, Ferdinand; Raubenheimer, Helgard G.
• Is Part Of: Chemphyschem. Volume 18:Issue 16(2017)
• Page Start: 2288
• Page End: 2294
• Publication Date: 2017-07-06
• Subjects: dihydrogen bonds -- Eigen complex analogues -- gold hydrides -- quantum chemical calculations -- σ-dihydrogen gold complexes; Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201700383
• Languages: English
• ISSNs: 1439-4235

Abstract

Abstract: Wavefunction and DFT calculations indicate that anionic dihydride complexes of Au I form strong to moderate directed Au−H⋅⋅⋅H bonds with one or two HF, H2 O and NH3 prototype proton donor molecules. The largely electrostatic interaction is influenced by relativistic effects which, however, do not increase the binding energy. Very weak Au⋅⋅⋅H associations—exhibiting a corresponding bond path—occur between neutral AuH and HF units, although ultimately F becomes the preferred donor atom in the most stable structure. Increasing the hydridicity of AuH by attachment of an electron donating NHC ligand effects Au‐H⋅⋅⋅H bonding of moderate strength only with HF, whereas competing Au⋅⋅⋅H interactions dominate for H2 O and NH3 . Rare η 2 coordinated and HX (X=F or OH) associated H2 complexes are produced during interaction with a single ion of stronger acidity, H2 F + or H3 O + . Theoretically, reaction of excess [AuH2 ] − as proton acceptor with H3 O + or NH4 + in 3:1 or 4:1 ionic ratios, respectively, affords H⋅⋅⋅H bonded analogues of Eigen‐type adducts. Outstanding analytical relationships between selected bonding parameters support the integrity of the results. Abstract : The strength of dihydrogen bond formation, as measured by binding energy E bind, between a range of gold(I) hydrides as proton acceptors and main group proton donors in various ratios, reflects the negative charge transferred (CT) from acceptor to donor upon association.