Protonation of Dppbz- and Binap-Ligated Rhodathiaboranes Yielding Hydron, Hydride, and Hydrogen Exchange

Vidondo, Javier (Universidad de Zaragoza) ; Urdániz, Laura ; Sanz Miguel, Pablo J. (Universidad de Zaragoza) ; Rodríguez, Ricardo ; Macías, Ramón (Universidad de Zaragoza)

Resumen: The reaction of the 11-vertex rhodathiaborane [8,8,8-(H)(PPh3)2-3-(NC5H5)-nido-7,8-RhSB9H10] (1) with 1,2-bis(diphenylphosphine)benzene (dppbz) and (S)-(−)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (binap) affords [1,1-(η2-dppbz)-3-(NC5H5)-closo-1,2-RhSB9H8] (2) and [1,1-(η2-binap)-3-(NC5H5)-closo-1,2-RhSB9H8] (3). These 11-vertex closo-rhodathiaborane chelates result from PPh3 ligand substitution at the rhodium center and a nido-to-closo structural cluster transformation driven by H2 loss. Treating compounds 2 and 3 with triflic acid (TfOH) leads to the formation of cationic clusters 4 and 5. The hydrons bind to the polyhedral clusters, acquiring hydride character and providing chemical nonrigidity that manifests through metal vertex-to-thiaborane pseudo-rotations and concomitant hydron tautomerisms. The resulting cations react with hydrogen to form mixtures of hydrons, hydrogen, and hydridorhodathiaboranes in equilibrium. The reaction products are the result of heterolytic cleavage of the H–H bond, with full participation of the clusters and the addition of hydrogen atoms to the cages. In these reactions, there is a conversion of electrons and hydrons into hydrogen, and hydrogen into hydride ligands, demonstrating that these boron-based metal compounds act as electron reservoirs, capable of promoting multielectron processes.

Idioma: Inglés

DOI: 10.1021/acs.inorgchem.4c02652

Año: 2024

Publicado en: Inorganic Chemistry 63, 42 (2024), 19593-19606
ISSN: 0020-1669

Financiación: info:eu-repo/grantAgreement/ES/DGA/E05-23R
Financiación: info:eu-repo/grantAgreement/ES/MCIU-AEI-FEDER/PID2021-122406NB-I00

Tipo y forma: Article (PostPrint)

Área (Departamento): Área Química Inorgánica (Dpto. Química Inorgánica)