Synthesis and Characterization of Bis(sigma)borate and Bis–zwitterionic Complexes of Rhodium and Iridium. Issue 13 (22nd August 2016)

• Record Type: Journal Article
• Authors: Roy, Dipak Kumar; Borthakur, Rosmita; De, Anangsha; Varghese, Babu; Phukan, Ashwini K.; Ghosh, Sundargopal
• Is Part Of: ChemistrySelect. Volume 1:Issue 13(2016)
• Page Start: 3757
• Page End: 3761
• Publication Date: 2016-08-22
• Subjects: boron -- bis(sigma)borate -- bis-zwitter -- iridium -- rhodium; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201600980
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: Building upon the chemistry of Rh–N, S‐heterocyclic carbene complex, [(Cp*Rh)(L2 )(1‐benzothiazol‐2‐ylidene)], 2 (Cp*=η 5 ‐C5 Me5 ; L=C7 H4 NS2 ) with various monoboranes‐Lewis adducts, we explored the chemistry of2 with BH3 ⋅thf at elevated temperature. As a result, mild thermolysis of2 with BH3 ⋅thf led to the formation of bis(sigma)borate [(η 4 ‐C5 Me5 H)Rh(η 2 ‐H3 BL)], 3 and a bis‐zwitterionic species [Cp*RhS(BH2 L2 )], 4 with the concomitant release of BH3 ⋅bt (bt=benzothiazole). The RhS3 C2 N2 B2 atoms in4 generates two six membered rings fused by a common Rh−S bond, which may be considered as a bicycle [4.4.0] cage at the rhodium center. In an effort to generate the iridium analogue of3, reaction of [Cp*IrCl2 ]2 with Na[H3 B(mbt)] (mbt=2‐mercaptobenzothiazole) was carried out that produced bis(sigma)borate complex [(η 4 ‐C5 Me5 H)Ir(η 2 ‐H3 BL)], 1 . The solid state X‐ray structures of1 and3 showed that the Cp*H ligand coordinated to the metal center in a η 4 ‐fashion. In compound3, the methyl group is oriented towards rhodium center, whereas it is away from Ir center in1 . In addition, the DFT computations were performed to shed light on the bonding and electronic structures of these compounds. Abstract : Bis(sigma)borate (A, B) and bis‐zwitterionic (C) complexes (see picture)