Oxidative Addition of Biphenylene and Chlorobenzene to a Rh(CNC) Complex

Amy E Kynman; Samantha Lau; Sean O Dowd; Tobias Krämer; Adrian B Chaplin

doi:10.1002/ejic.202000780

Oxidative Addition of Biphenylene and Chlorobenzene to a Rh(CNC) Complex

Eur J Inorg Chem. 2020 Nov 8;2020(41):3899-3906. doi: 10.1002/ejic.202000780. Epub 2020 Oct 20.

Authors

Amy E Kynman¹, Samantha Lau¹, Sean O Dowd², Tobias Krämer^{2

3}, Adrian B Chaplin¹

Affiliations

¹ Department of Chemistry University of Warwick Gibbet Hill Road Coventry CV4 7AL UK.
² Department of Chemistry Maynooth University Co. Kildare Maynooth Ireland.
³ Hamilton Institute Maynooth University Co. Kildare Maynooth Ireland.

Abstract

The synthesis and organometallic chemistry of rhodium(I) complex [Rh(CNC-Me)(SOMe₂)][BAr^F ₄], featuring NHC-based pincer and labile dimethyl sulfoxide ligands, is reported. This complex reacts with biphenylene and chlorobenzene to afford products resulting from selective C-C and C-Cl bond activation, [Rh(CNC-Me)(2,2'-biphenyl)(OSMe₂)][BAr^F ₄] and [Rh(CNC-Me)(Ph)Cl(OSMe₂)][BAr^F ₄], respectively. A detailed DFT-based computational analysis indicates that C-H bond oxidative addition of these substrates is kinetically competitive, but in all cases endergonic: contrasting the large thermodynamic driving force calculated for insertion of the metal into the C-C and C-Cl bonds, respectively. Under equivalent conditions the substrates are not activated by the phosphine-based pincer complex [Rh(PNP-iPr)(SOMe₂)][BAr^F ₄].

Keywords: Computational analysis; DFT calculations; Oxidative addition; Pincer ligands; Rhodium.