Heterobimetallic RePd complexes bridged by η1:η5-Ph2PC5H4 ligand. Synthesis, electronic and crystal structure of (CO)2(PR3)(η5-C5H4PPh2)Re–PdCl2, R = Me and OMe

Abstract

The new rhenium complexes (η⁵-C₅H₄PPh₂)Re(CO)₂(PR₃) (R = Me (1) and OMe (2)) were prepared photochemically from (η⁵-C₅H₄PPh₂)Re(CO)₃ in the presence of PMe₃ or P(OMe)₃. Further reaction of these ligands with PdCl₂(NCPh)₂ in chloroform, produces the heterobimetallic complexes (CO)₂(PMe₃)(η⁵-C₅H₄PPh₂)Re–PdCl₂ (3) and (CO)₂(P(OMe)₃)(η⁵-C₅H₄PPh₂)Re–PdCl₂ (4). IR spectroscopy reveals that both complexes possess a Re–Pd interaction which was confirmed by X-ray crystallography (Re–Pd bond distance = 2.762 Å in 3 and 2.774 Å in 4). Relativistic functional density theory calculations have also been carried out in order to probe the bonding in these compounds.