Crystal Structures And Properties Of Complexes Based On4’-(4’’-pyridyl)-2,2’:6’2’’-terpyridine

During the last decade much effort has been devoted to the preparation ofsupramolecular assemblies[1]and coordination polymers[2]. Whereas the basic principle ofcombining the building blocks of metal cations with preferred arrangements and carefullydesigned multidentate ligands to form predetermined structures seems intriguingly simple,countless subtle factors influence the formation of the final product, often limiting theenvisioned predictability of this approach. Each newly characterized structure, whether itformed according to prediction or not, gets us one step closer to understand the manyunderlying principles in the formation of this fascinating type of material. We have focused onthe design and the synthesis of a series of functionalized tepryridines and their transitionmetal compounds. The synthesis of these compounds may provide a new approach for theconstruction of coordination polymers of4’-（4’’-pyridyl）₂,2’:6’2’’-Terpyridine （L）. In thispaper,7complexes as following:[Cd（HBTC）（L）（H₂O）]·2H₂O （1）[Cd（1,4-BDC）_0.5（L）（H₂O）₂]·0.5（1,4-BDC）（5）[Cu（HBTC）（L）]·L （2）[Cu（1,4-BDC）_0.5（L）（H₂O）]·0.5（1,4-BDC）·4H₂O （6）[Zn（HBTC）（L）]·L （3） Zn₂（1,4-BDC）₂（L）₂（7）[Co（HBTC）（L）（H₂O）₂]·H₂O （4）（H₃BTC=1,3,5-Benzenetricarboxylic acid,1,4-H₂BDC=Terephthalic acid）。In complexes1-3, two kinds of HBTC carboxylic bridges are found between MII ions toform a1D chain and further construct3D structure by hydrogen bonds. Compound4ismononuclear molecules, which are further linked into a3D supramolecular framework viaO-H···N and O-H···O hydrogen bonds.The compounds5-7are all mononuclear molecules, but compounds5and6are furtherlinked into a3D supramolecular framework via O-H···N and O-H···O hydrogen bonds whilecompound7is assembled into a3D network structure through Ï€-Ï€ interactions only.