The reactivity of an unsaturated, cationic (C5Me5)Ir(III) complex (2(Xyl)+) bearing the xylyl-substituted terphenyl phosphine PMe2ArXyl2 (ArXyl2 = C6H3-2,6-(C6H3-2,6-Me2)2) towards triethylamine (NEt3) is studied and compared to our previous investigations based on the related complex 2(Dipp)+ containing the bulkier phosphine PMe2ArDipp2 (ArDipp2 = C6H3-2,6-(C6H3-2,6-iPr2)2). Low-temperature multinuclear NMR studies support the formation of a C–C bond between the deprotonated C5Me5 ligand and a flanking xylyl ring of the phosphine, which becomes dearomatized (complex 4(Xyl)+). Interestingly, this complex presents divergent reactivity relative to the bulkier diisopropylphenyl counterpart, undergoing formal addition of HCl to yield complex 5(Xyl)+, isomeric to the starting complex 2(Xyl)+. These transformations are rationalized by means of Density Functional Theory (DFT) calculations.
- Terphenyl phosphine
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry