A synthon for a 14-electron Ir(iii) species: catalyst for highly selective β-(Z) hydrosilylation of terminal alkynes

A synthon for a 14-electron Ir(III) species is described. The geometrical control exerted by the ligand system over the Ir-alkenyl intermediate in hydrosilylation of terminal alkynes precludes formation of the more thermodynamically stable β-(E)-vinylsilane, thus affording the β-(Z) isomer in excellent yields.