CATALYTIC C-H OLEFIN COUPLING

Several ruthenium complexes have been found to catalyze the addition of the C-H bond of arenes to olefins. Phenyl methyl ketone undergoes addition at its ortho position across the double bond of trimethylvinylsilane in the presence of a catalytic amount of RuH2(CO)(PPh3)3 to give 1 : 1 and 1 : 2 coupling products. In the latter, the two ortho hydrogens have reacted. Similarly, 2-methylphenyl methyl ketone reacts with trimethylvinylsilane and triethoxyvinylsilane to give the corresponding 1 : 1 coupling products in virtually quantitative yields. The results represent a breakthrough in the chemistry of carbon-hydrogen bond cleavage by metal complexes.