Synthesis and Structure of the {(2-Phosphinoethyl)silyl}- tris(tertiary phosphine)iridium(I) Complex Ir{η²-Me₂Si(CH₂)₂PPh₂}(PMe₃)₃

The hydridomethyl(silyl)iridium(III) complex Ir(H)(Me){η 2 -Me 2 Si(CH 2 ) 2 PPh 2 }(PMe 3 ) 2 ( 2 ) reacted quantitatively with PMe 3 at 60 °C to give the {(2-phosphinoethyl)silyl}tris(tertiary phosphine)iridium(I) complex Ir{η 2 -Me 2 Si(CH 2 ) 2 PPh 2 }(PMe 3 ) 3 ( 3 ) as reddish orange crystals through the reductive elimination of methane. X-ray crystal structure analysis revealed that 3 adopts a slightly distorted five-coordinate, trigonal-bipyramidal geometry with the silyl ligand occupying an axial site. Complex 3 generates the 16e silyliridium(I) complex Ir{η 2 -Me 2 Si(CH 2 ) 2 PPh 2 }(PMe 3 ) 2 ( A ) easily at room temperature.