The reactions of M(pnp)Cl2 [M = Pd, Pt; pnp = 2,6-bis(diphenylphosphinomethyl)pyridine] and Pt(dppf)Cl2 [dppf = 1,1'-bis(diphenylphosphinomethyl)ferrocene] with NaOMe in MeOH under CO at room temp. and atm. pressure were examd. In contrast to the behavior of the Pt(dppf)Cl2 complex, which gave the corresponding bis(methoxycarbonyl) compd., the terdentate ligand of the M(pnp)Cl2 complexes was nucleophilically attacked by the methoxide ion to lose a proton and yield [MX{C5H3N(CHPPh2)(CH2PPh2)}] (M = Pt, X = Cl, COOMe; M = Pd, X = COOMe), which were characterized by chem. and spectroscopic means. X-ray anal. of both title complexes showed that the terdentate anionic ligand chelates the metal to form two 5-membered rings, and the P-C and C-C bond lengths in one of the chelate rings agree with an sp2 hybridization of the formally anionic methylenidic carbon and with a large delocalization in the ring.
Syntheses and structures of 2-diphenylphosphinomethylenide-6-diphenylphosphinomethylenepyridine complexes of palladium(II) and platinum(II). Crystal structures of [PtCl[2-(CHPPh2)-6-(CH2PPh2)pyridine]] and [Pd(COOMe)[2-(CHPPh2)-6-(CH2PPh2)pyridine]]
VASAPOLLO, Giuseppe;
1988-01-01
Abstract
The reactions of M(pnp)Cl2 [M = Pd, Pt; pnp = 2,6-bis(diphenylphosphinomethyl)pyridine] and Pt(dppf)Cl2 [dppf = 1,1'-bis(diphenylphosphinomethyl)ferrocene] with NaOMe in MeOH under CO at room temp. and atm. pressure were examd. In contrast to the behavior of the Pt(dppf)Cl2 complex, which gave the corresponding bis(methoxycarbonyl) compd., the terdentate ligand of the M(pnp)Cl2 complexes was nucleophilically attacked by the methoxide ion to lose a proton and yield [MX{C5H3N(CHPPh2)(CH2PPh2)}] (M = Pt, X = Cl, COOMe; M = Pd, X = COOMe), which were characterized by chem. and spectroscopic means. X-ray anal. of both title complexes showed that the terdentate anionic ligand chelates the metal to form two 5-membered rings, and the P-C and C-C bond lengths in one of the chelate rings agree with an sp2 hybridization of the formally anionic methylenidic carbon and with a large delocalization in the ring.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
