Hydrogenation reactions with RuCl 2(L-L) 2 (L-L = bidentate phosphine) Part II

Abstract

The compounds with general formula RuCl 2(L-L) 2 (L-L bidentate phosphine, Ph 2P(CH 2) n PPh 2, n = 4, 5, 6) catalytically hydrogenate unsaturated organic substrates such as olefins, dienes, aldehydes and ketones under moderate reaction conditions in polar solvents, even in the absence of NH 4 + salts. In general the catalytic activity follows the order n = 4 > n = 6 > n = 5. Small percentages of isomerization products of the terminal olefin are observed, which increase with the value of n. With 1,5-cyclooctadiene, the hydrogenation to the monoene is faster than the second hydrogenation, and follows the order n = 4 > n = 5 > n = 6.