Biphase systems were generated by combining toluene solutions of alkenes (2-cyclohexen-1-one, 1-dodecene, cyclododecene, 4-bromostyrene) and CF3C6F11 solutions of the pre-catalyst ClRh[P(CH2CH2(CF2)(5)CF3)(3)](3) ((1); 1.1-0.8 mol%) and placed under 1 atm of H-2. The perfluoroalkyl segments in (1) confer high affinities for fluorocarbons. After 8-26 h at 45 degrees C, the CF3C6F11 phases were separated, and extracted with an equal volume of toluene. GLC analyses of the toluene solutions showed 98-87% yields of the hydrogenation products cyclohexanone, dodecane, cyclododecane, and 4-bromoethylbenzene (turnover numbers 120-87). The CF3C6F11 phases were charged with new toluene solutions of 2-cyclohexen-1-one or 1-dodecene, and similarly treated with H-2. There was no significant loss of catalyst activity over three cycles. A preparative reaction gave cyclohexanone in 89% yield. Some C=C isomerization could be detected during the course of 1-dodecene hydrogenation, and (1) gave a dihydride complex in the absence of alkene.