STERICALLY RESTRICTIVE METAL-COMPLEXES - THE SYNTHESIS AND STRUCTURALCHARACTERIZATION OF LPYRIDIN-2-YL)ETHANE-N,N')-(MALONATO)PALLADIUM(II) TRIHYDRATE - PROTON NMR BINDING-STUDIES TO CYTOSINE AND GUANINE DERIVATIVES

Two different routes for the preparation of the bidentate ligand 1,2-b is(6-methylpyridin-2-yl)ethane (bmpe) have been explored and are descr ibed. 1:1 coordination of this ligand with palladium(II) and the isola tion of crystals of the complex as the malonate trihydrate has allowed the crystal and molecular structure to be determined. The compound cr ystallizes in space group P2(1)/n with a=12.946(1), b=7.431(1), c=20.4 83(2) angstrom, beta=91.941(3)-degrees, Z=4. The structural analysis r eveals that the 6-methyl groups of the bidentate bmpe ligand both proj ect over one side of the square-plane, effectively blocking it off. Th e interaction of the Pd(bmpe)2+ complex cation with cytosine and guani ne derivatives has been investigated by proton NMR spectroscopy.