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<i>N</i>,<i>O</i>-chelating dicarbonylhydrazido-palladium complexes were synthesized by treatment of 1,2-bis(trifluoroacetyl)hydrazine with a mixture of a Pd(0) source, [Pd(dba)₂] (DBA = dibenzylideneacetone), and four-electron donors including 1,3-bis(diphenylphosphino)propane (DPPP), <i>N</i>,<i>N</i>,<i>N</i>’,<i>N</i>’-tetramethylethylenediamine (TMEDA), and two equivalents of triphenylphosphine. The same products from DPPP and TMEDA could be obtained alternatively by using Pd(OAc)₂ through deprotonation of the diacylhydrazine. The five-membered chelate structure was confirmed by NMR spectra and X-ray crystal structure determination. The X-ray structures indicate that the products are formally considered as Pd(II) complexes with a hydrazido(2–) ligand. In the case of the triphenylphosphine-coordinated complex, a fluxional behavior in dichloromethane-<i>d</i>₂ was observed by variable temperature NMR experiments, possibly due to structural changes between the square planar and pseudo-tetrahedral geometries.