A new imine ligand avoiding imine–enamine rearrangement and cyclometallation: Synthesis and coordination of Me3C6H2CH2Ndouble bond; length as m-dashCHtBu

The new imine ligand (E)-2,4,6-Me3C6H2CH2Ndouble bond; length as m-dashCHtBu (1) has been prepared from 2,4,6-trimethylbenzylamine and trimethylacetaldehyde. In this imine, the ortho-positions of the benzyl group are blocked by methyl groups, and there are no β-hydrogen atoms susceptible for imine–enamine rearrangement. Thus, reaction with [PdCl2(C6H5CN)2] leads to the complex trans-[PdCl2(2,4,6-Me3C6H2CH2Ndouble bond; length as m-dashCHtBu)2] (2) that cannot undergo cyclopalladation. The single-crystal X-ray structure analysis of trans-[PdCl2(2,4,6-Me3C6H2CH2Ndouble bond; length as m-dashCHtBu)2] (2) confirms the trans-coordination of the imine ligands in this square-planar complex.