267876-56-2Relevant academic research and scientific papers
Platinum(n), palladiuni(n) and rhodium(i) complexes of o-, m- And P-Ph2PC6H4PO(OEt)2. PtCl2-SnCl2 Hydroformylation catalysts modified with phosphonated triarylphosphines
Ellis, Dianne D.,Harrison, Gayle,Guy Orpen,Phctmung, Hirihattaya,Pringle, Paul G.,Dcvries, Johannes G.,Oevering, Henk
, p. 671 - 675 (2007/10/03)
An improved route to the bulky phosphine o-Ph2PC6H4PO(OEt)2 o-l has been elaborated. The isomers [PtCl2L2], L = o- (2), m- (3) or p-l (4), were made by treatment of [PtCl2(cod)] with the appropriate phosphine. Complex 2 has a trans configuration whereas the m and p isomers, 3 and 4 are cis, reflecting the greater bulk of the o isomer. Crystal structure analyses of o-1 and its platinum complex 2 indicated normal dimensions for the tertiary phosphine in both and the considerable asymmetric steric bulk of o-l. Abstraction of the chloro ligands in 2 occurs upon addition of AgSbF6 and the resulting dicationic bis P,O-chelate 5 has a cis geometry. The palladium complexes [PdCl2L2], L = o- (6), m- (7), orp-1 (8) were made by treatment of [PdCl2(NCPh)J with the appropriate phosphine but, in contrast to the platinum analogues, the o isomer 6 has a cis configuration and the 7 and p isomers 7 and 8 are predominantly trans. Complex 6 is fluxional: variable temperature 31P NMR spectroscopy is consistent with hemilabile behaviour of the ligand with reversible co-ordination of the P=O of the phosphonate functionality. Treatment of [Rh2Cl2(CO)4] with o-1 gave the mononuclear chelate [RhCl(CO)(o-1)] (9) which upon addition of further o-l gave predominantly the fluxional species trans-[RhCl(CO)(o-l)J. The platinum complexes 2,3 and 4 when combined with SnCl2 catalyse the hydroformylation of but-2-ene and but-1-ene. The Royal Society of Chemistry 2000.
