Alkyl, hydrido and related compounds of ruthenium with trimethylphosphine and bis(1,2-dimethylphosphino)ethane. X-ray crystal structures of cis-hydridoethyltetrakis(trimethylphosphine)-ruthenium(II) and ethylene tetrakis-(trimethylphosphine)ruthenium(0)

Abstract

The interaction of trans-RuCl 2(PMe 3) 4 with R 2Mg, depending on the reaction conditions and the alkyl groups gives either (C 2H 4)Ru(PMe 3) 4 or cis-Ru(H)(C 2H 5)(PMe 3) 4 for R = ethyl, and cis-Ru(H)( n C 3H 7(PMe 3) 4 for R = n-propyl. The interaction of Et 2Mg with trans-RuX 2(dmpe) 2 (X = Cl, CO 2Me) gives either cis-Ru(Et 2)dmpe) 2 for X = Cl or trans-Ru(Et) 2(dmpe) 2 for X = CO 2Me. NMR data for (C 2H 4)Ru(PMe 3) 4 suggest that ethylene is bound in the η 2 or metallocyclopropane form, which is confirmed by a single-crystal X-ray diffraction study. This shows a relatively long carbon-carbon bond distance of 1.44(1)Å between the “ethylene” carbons. The structure of cis-Ru(H)(C 2H 5)(PMe 3) 4 has also been confirmed by a single-crystal X-ray diffraction study. Possible mechanisms for the observed reactivities are considered.