Hydrosilylation catalysed by a rhodium complex in a supercritical CO2/ionic liquid system

The hydrosilylation of alkenes in a supercritical CO2 (scCO(2))/ionic liquid (IL) system was investigated. Rh(PPh3)(3)Cl exhibited excellent catalytic activity and selectivity. (KOBu)-Bu-t was used as an additive, and no hydrogenation by-product (alkane) was detected in the scCO(2)/IL system. During hydrosilylation in the scCO(2)/IL system, the reactants were possibly transferred into the IL phase by scCO(2), in which the catalyst was dissolved. The products can be flushed with scCO(2) after the reaction and the catalyst/IL system reused.