Metal-Involving Halogen Bonding Including Gold(I) as a Nucleophilic Partner. The Case of Isomorphic Dichloroaurate(I)·Halomethane Cocrystals

Irina S Aliyarova; Elena Yu Tupikina; Daniil M Ivanov; Vadim Yu Kukushkin

doi:10.1021/acs.inorgchem.1c03482

Metal-Involving Halogen Bonding Including Gold(I) as a Nucleophilic Partner. The Case of Isomorphic Dichloroaurate(I)·Halomethane Cocrystals

Inorg Chem. 2022 Feb 7;61(5):2558-2567. doi: 10.1021/acs.inorgchem.1c03482. Epub 2022 Jan 24.

Authors

Irina S Aliyarova¹, Elena Yu Tupikina¹, Daniil M Ivanov¹, Vadim Yu Kukushkin^{1

2}

Affiliations

¹ Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9, Saint Petersburg 199034, Russian Federation.
² Institute of Chemistry and Pharmaceutical Technologies, Altai State University, Barnaul 656049, Russian Federation.

PMID: 35073483
DOI: 10.1021/acs.inorgchem.1c03482

Abstract

Three isomorphic cocrystals were obtained via the crystallization of [PPN][AuCl₂] (1) from CHBr₃ (1·CHBr₃), or CHCl₃/1,2-C₂F₄Br₂ (1·CHCl₃) and CH₂Cl₂/Et₂O (1·CH₂Cl₂) mixtures. Analysis of the single-crystal X-ray diffraction data for these cocrystals revealed a gold(I)-involving two-center C-X···Au halogen bond (abbreviated as XB; X = Cl, Br) and a three-center bifurcated C-Br···(Cl-Au) XB; in the latter, the gold(I)-chloride linkage functions as an integrated XB acceptor. The noncovalent nature and energies [spanning from -1.58 to -5.52 kcal/mol for C-X···Au and -6.37 kcal/mol for C-Br···(Cl-Au) XBs] of these noncovalent interactions were studied by density functional theory calculations and topological analysis of the electron density distribution in the framework of the quantum theory of atoms-in-molecules (QTAIM) followed by noncovalent interaction (NCI) analysis at the B3LYP-D3/jorge-TZP-DKH level of theory. The nucleophilicity of the gold(I) centers toward halogens of halomethanes was verified by a set of independent methods including electrostatic potential surfaces, electron localization function projection, natural bond orbital charge transfer, electron density/electrostatic potential profile, Wiberg bond indexes, natural population analysis, and atoms-in-molecules charge analyses.