A reaction of RhH2(O2COH)(P(i-Pr)3)2 (1) with PhO=CPh has been found to give trans-stilbene and a novel binuclear rhodium complex RH2H2(O2CO)(PhC=CPh)(P(i-Pr)3)3 (2). A similar reaction with MeO2CC=CCO2Me results both in H2 evolution and half-hydrogenation, while with F3C=CCF3 only H2 evolution is observed. Compound 1 catalyzes the stereoselective half-hydrogenation of alkynes to trans olefins. Complex 2 crystallizes in the monoclinic space group C52h/P21/c,, with four formula units in a cell of dimensions a = 17.158 (4) Å, b = 23.916 (3) Å, c = 11.255 (3) Å, β = 103.3 (1)°, and V = 4494 Å3 (t ≍ -160 °C). In the solid state 2 consists of a distorted octahedral Rh(III) center and a distorted square-planar Rh(I) center bridged by a bis-bidentate carbonato group.
ASJC Scopus subject areas
- Colloid and Surface Chemistry