Chemistry of acetoacetanilide and derivatives with zero-and di-valent platinum and palladium complexes; crystal structure of the four-membered ring palladalactam complex [Pd{CH(COMe)C(O)NPh}(bipy)](bipy = 2,2′-bipyridyl)

Abstract

Reaction of the complexes cis-[MCl₂L₂][M = Pd, L₂= 2,2′-bipyridyl (bipy); M = Pt, L = PPh₃ or L₂= cycloocta-1,5-diene or Ph₂P(CH₂)₃PPh₂] with acetoacetanilide, o- or p-acetoacetanisidide mediated by silver(I) oxide gave, under mild conditions, high yields of the metallalactam complexes [[graphic omitted]R}L₂](R = Ph, C₆H₄OMe-o or p). The complexes have been fully characterised by multinuclear NMR spectroscopy, fast atom bombardment mass spectrometry, and by a single-crystal X-ray diffraction study carried out on the 2,2′-bipyridyl palladium derivative [[graphic omitted]Ph}-(bipy)]. The complex contains a slightly puckered palladalactam ring system (fold angle 17.5°). Reaction of acetoacetanilide with the zerovalent platinum complex [Pt(trans-PhCHCHPh)(PPh₃)₂] in air gives exclusively the peroxometallacyclic complex [[graphic omitted]}(PPh₃)₂], while reaction with [Pt(PPh₃)₄] gave a mixture of the peroxometallacycle plus the platinalactam complex [[graphic omitted]Ph}(PPh₃)₂].