MN(CO)5C(O)-P-C6H5CH3-CATALYZED HYDROSILANE SIH SID EXCHANGE - EVIDENCE FROM A KINETICS STUDY IMPLICATING COORDINATIVELY UNSATURATED MANGANESE SILYL INTERMEDIATES/

The manganese p-toluoyl complex Mn(CO)5C(O)-p-CH3C6H4 catalyzes SiH/Si D exchange between DSiMe2Ph and HSiMe2Et at room temperature in C6D6. The preequilibrium kinetics are consistent with a second-order isotope exchange reaction; plots of initial velocities nu0 against [HSiMe2Et] i further established saturation kinetiCs. Lineweaver-Burk plots are i n accord with a ping-pong bi-bi mechanism that operates under rapid eq uilibrium conditions and involves coordinatively unsaturated manganese silyls, (CO)4MnSiMe2R, as active catalysts.