Bis‐Anagostic Structures in N,N’‐Chelate Ligand Complexes of Palladium(II)

Abstract

AbstractReaction of N,N’‐dibenzylidene‐2,2‐dimethylpropylenediamine with Pd(OAc)2produces essentially one product which NMR spectroscopy indicates has abis‐anagostic structure. A density functional theory (DFT) calculation shows that in the square planar structure, both aromatic rings lie above the coordination plane with close approaches of twoortho‐C−H bond hydrogens to both the Pd centre and the two acetato ligand coordinating oxygen atoms. N,N’‐dibenzylideneethylenediamine reacts with Pd(OAc)2similarly where abis‐anagostic structure is indicated by NMR spectroscopy and a DFT calculation shows an energy preference for an above plane positioning of the two aromatic rings. N,N,N’,N’‐tetrabenzylethylenediamine reacts with Pd(OAc)2to give a structure which X‐ray crystallography shows two benzyl phenyl groups lie above and below the coordination plane respectively.