New synthetic route, X-ray structure, and molecular orbital analysis for trans,trans-dichlorobis(triphenylphosphine)(phenyl)rhodium(III). Do agostic Rh***H(PPh3), hydrogen-bond (Rh)Cl***H(PPh3), or steric intramolecular interactions prevail?

A two-step, high-yield synthesis of (RhCl2-(Ph)(PPh3)2) starting from RhCl3*3H2O and SbPh3 through (RhCl2(Ph)(SbPh3)3), a density functional analysis with geometry optimization of the model molecule (RhCl2(PH)(PH2CHCH2)2) and an X-ray analysis of the monoclinic crystals is described. Results demonstrate a new efficient, synthetic route to stable organometallic compounds which can serve as starting materials for various preparative strategies.