Can Copper(I) and Silver(I) be Hydrogen Bond Acceptors?

0568888 - ÚOCHB 2024 RIV DE eng J - Journal Article
Andris, Erik - Straka, Michal - Vrána, J. - Růžička, A. - Roithová, J. - Rulíšek, Lubomír
Can Copper(I) and Silver(I) be Hydrogen Bond Acceptors?
Chemistry - A European Journal. Roč. 29, č. 26 (2023), č. článku e202203769. ISSN 0947-6539. E-ISSN 1521-3765
Research Infrastructure: e-INFRA CZ - 90140
Institutional support: RVO:61388963
Keywords : copper * density functional calculations * gold * hydrogen bond * ion spectroscopy * IR spectroscopy * silver
OECD category: Physical chemistry
Impact factor: 4.3, year: 2022
Method of publishing: Open access
https://doi.org/10.1002/chem.202203769

Gold(I) centers can form moderately strong (Au⋅⋅⋅H) hydrogen bonds with tertiary ammonium groups, as has been demonstrated in the 3AuCl+ (3+=1-(tert-butyl)-3-phenyl-4-(2-((dimethylammonio)methyl)phenyl)-1,2,4-triazol-5-ylidene) complex. However, similar hydrogen bonding interactions with isoelectronic silver(I) or copper(I) centers are unknown. Herein, we first explored whether the Au⋅⋅⋅H bond originally observed in 3AuCl+ can be strengthened by replacing Cl with Br or I. Experimental gas-phase IR spectra in the ∼3000 cm−1 region showed only a small effect of the halogen on the Au⋅⋅⋅H bond. Next, we measured the spectra of 3AgCl+, which exhibited significant differences compared to its 3AuX+ counterparts. The difference has been explained by DFT calculations which indicated that the Ag⋅⋅⋅H interaction is only marginal in this complex, and a Cl⋅⋅⋅H hydrogen bond is formed instead. Calculations predicted the same for the 3CuCl+ complex. However, we noticed that for Ag and Cu complexes with less flexible ligands, such as dimethyl(2-(dimethylammonio)phenyl)phosphine (L7H+), the computations predict the presence of the respective Ag⋅⋅⋅H and Cu⋅⋅⋅H hydrogen bonds, with a strength similar to the Au⋅⋅⋅H bond in 3AuCl+. We, therefore, propose possible complexes where the presence of (Ag/Cu)⋅⋅⋅H bonds could be experimentally verified to broaden our understanding of these unusual interactions.
Permanent Link: https://hdl.handle.net/11104/0340164


Research data: CCDC, CCDC