Ruthenium Carbonyl Complexes as Homogeneous Catalysts for X-H Activation (X = C, N, O, Si)

Abstract

Ruthenium carbonyl complexes have been used as catalyst for the activation of unreactive X-H bonds (X = C, O and Si). Trinuclear Ru (0) clusters, mononuclear Ru (0)-diene complexes, and mononuclear Ru (0)-phosphine complexes catalyze the addition of carboxylic acids across alkynes. By controlling the ligands, either the trans or geminal-products can be generated in high yields. Dimeric Ru (II) complexes catalyze the Markovnikov addition of pyrroles across alkynes. This reaction proceeds specifically via the activation of the aromatic C-H bond, and not the N-H bond, to produce 2-vinylpyrroles in high yields. In the third section, the same dimeric Ru (II) complexes activate the relatively strong Si-H bond of silanes to produce hydrogen gas and silanol in the presence of H2O. TON and TOF of more than 104 and 40 min-1 have been achieved at room temperature.