Synthesis, characterization and X-ray structures of the model ligand for acoordination polymer: diethyl-2, 6-pyridine dicarboxamide and its complex with PdCl2

The reaction of 2,6-dicarboxylic acid dichydrochloride in dry toluene with EtNH2 in KOH affords the title compound (I). It is a model ligand to mimic the polymer repeat unit to establish the site of metal coordination to poly mer support. The central part of the molecule constitutes of a pyridine rin g with two side chains forming an inner cavity with two hydrogen amide atom s pointing towards the cavity. The pyridine nitrogen atom completes the thi rd potential binding site. The carbonyl groups are directed outside of the inner cavity. The reaction of I with a stoichiometric amount of dichlorobis (benzonitrile) palladium in CH2Cl2 affords the [bis(diethyl-2,6-pyridine d icarboxamide)Pd2Cl6]. 2HCl (II). Compounds I and II were fully characterize d by spectroscopic techniques and also by X-ray diffraction analysis. (C) 2 001 Elsevier Science B.V. All rights reserved.