The ruthenium and iridium coordination chemistry of the tripodal ligand CH 3 C{CH 2 P( m -CF 3 C 6 H 4 ) 2 } 3

The ruthenium(II) complexes [Ru(CF 3 CO 2 ) 2 (CF 3 triphos)], [Ru 2 (μ-Cl) 3 (CF 3 triphos) 2 ]Cl, [RuH(CH 3 CN) 2 (CF 3 triphos)](CF 3 SO 3 ) and [Ru(CH 3 CN) 3 (CF 3 triphos)](CF 3 SO 3 ) 2 (CF 3 triphos=CH 3 C{CH 2 P( m -CF 3 C 6 H 4 ) 2 } 3 ) were prepared and characterized. The iridium complexes [Ir(COD)(CF 3 triphos)] +, [IrCl(CO)(CF 3 triphos)], [Ir(CO) 2 (CF 3 triphos)] +, [IrCl 3 (CF 3 triphos)] and [IrCl 3−n (MeCN) n (CF 3 triphos)](CF 3 SO 3 ) n ( n =1, 2 and 3) were also prepared and characterized. The coordination chemistries of these two elements with CF 3 triphos and with the unsubstituted ligand CH 3 C{CH 2 P(C 6 H 5 ) 2 } 3 (Htriphos) are compared. It is shown that, relative to Htriphos, CF 3 triphos (a) stabilizes the iridium(I) relative to the iridium(III) oxidation state and (b) its cationic complexes are stronger Lewis acids.