Phosphine substituted Ru3(μ-dppm)(CO)10: structural trends within [Ru3(μ-dppm)(PR3)(CO)9] (R=Et, Ph, Cy and Pri)

The complexes [Ru3(μ-dppm)(PR3)(CO)9] (R=Et, Ph, Cy, Pri} were prepared from [Ru3(μ-dppm)(CO)10] by simple phosphine substitution reactions at room temperature and their structures determined by single crystal X-ray studies. Variations in the RuRu bond adjacent to the phosphine ligand suggest the enhanced reactivity of [Ru3(μ-dppm)(CO)10] over the parent carbonyl [Ru3(CO)12] to be consequent on the inability of [Ru3(μ-dppm)(CO)10] to effectively relieve steric congestion imposed by the presence of the bulky, bidentate dppm ligand.