Different Coordination Modes of the Polyfunctional Ylide Ph3P=C(H)C(O)CH2C(O)OEt: C- vs. O,O′-Bonding in PdII, PtII and AuI Complexes

✍ Scribed by Marta Carbó; Larry R. Falvello; Rafael Navarro; Tatiana Soler; Esteban P. Urriolabeitia

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 218 KB
• Volume: 2004
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200300801

✦ Synopsis

Abstract

Treatment of the polyfunctional ylide Ph~3~P=C(H)C(O)CH~2~COOEt (1) with the solvated complexes [M(C^∧^X)(THF)~2~]ClO~4~ gave the O,O′ derivatives [M(C^∧^X)(Ph~3~PCH~2~C(O)=C(H)−C(=O)OEt‐κ‐O,O′]ClO~4~ [M(C^∧^X) = Pd(C~6~H~4~CH~2~NMe~2~) (2), Pd(CH~2~C~9~H~6~N) (3), Pd(NC~5~H~4~‐2‐C~6~H~4~) (4), Pd(NC~13~H~8~) (5), Pd[(S)−C~6~H~4~C(H)MeNMe~2~] (6), Pt[__o‐__CH~2~C~6~H~4~P(__o‐__tol)~2~] (7), Pd[__o‐__CH~2~C~6~H~4~P(__o‐__tol)~2~] (8), and Pd(C~6~F~5~)(SC~4~H~8~) (9)]. During the reaction, one proton of the methylene unit is transferred to the ylidic carbon, which is transformed into a phosphonium group generating the zwitterion [Ph~3~PCH~2~C(O)=C(H)−C(=O)OEt], which coordinates to the metal center as an O,O′‐chelating ligand. Treatment of 1 with [AuCl(SC~4~H~8~)] or [Au(PPh~3~)(OCMe~2~)]ClO~4~ gave [AuCl{C(H)(PPh~3~)C(O)CH~2~COOEt}] (10) or [Au{C(H)(PPh~3~)C(O)CH~2~COOEt}(PPh~3~)]ClO~4~ (11), in which the ylide is C‐bonded. The X‐ray crystal structures of complexes 2a, 9 and 10 have been determined. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)