New chiral thioether-phosphite ligands and their rhodium-coordination chemistry: steric and electronic properties, dynamic processes and application in catalysis. Issue 8 (7th May 2021)

• Record Type: Journal Article
• Authors: Major, Máté M.; Balogh, Szabolcs; Simon, József; Bakos, József; Farkas, Gergely
• Is Part Of: Journal of coordination chemistry. Volume 74:Issue 8(2021)
• Page Start: 1311
• Page End: 1322
• Publication Date: 2021-05-07
• Subjects: Thioether-phosphite -- phosphine-phosphite -- selective exchange -- stereoselective coordination -- rhodium -- asymmetric hydrogenation; Coordination compounds -- Periodicals; 541.2242
• DOI: 10.1080/00958972.2021.1892086
• Languages: English
• ISSNs: 0095-8972

Abstract

Abstract: Thioether-phosphite ligands (SP's) with axially chiral ( S )-H0 - or ( S )-H8 -binaphthyl moiety and their [Rh(COD)(SP)]BF4 complexes have been synthesized to study their coordination chemistry and catalytic features and to compare them to those of the structurally analogous phosphine-phosphites (PP's). NMR exchange studies on [Rh(COD)(SP)]BF4 complexes showed selective 1, 5-cyclooctadiene dynamics. Firm evidence has been found that this fluxional process involves dissociation of the Rh-sulfur bond. Based on in situ NMR studies, SP ligands can form two types of bis -ligated species at ligand-to-metal ratio higher than 1. Unlike bis -ligated phosphine-phosphite complexes, bis -ligated thioether-phosphite Rh-complexes can efficiently catalyze asymmetric hydrogenation reactions due to their distinct coordination chemistry. Graphical Abstract: