Transformation of mixed anionic coordination polymers of lead

摘要

The coordination polymerization from lead(II) nitrate on reaction with 4-nitrobenzoic acid and pyridine N-oxide at room temperature passes through stepwise ligand substitution reaction. An intermediate polymer [Pb(NB)(PyO)_2(NO_3)]_n (where NB = 4-nitrobenzoate, PyO = Pyridine N-oxide) is formed to give the final polymer [Pb(NB)_2(Py0)]_n. A hydrated mononuclear complex [Pb(NB)_2(Py0)(H_20)] is also formed if rigorous anhydrous condition is not maintained. The reaction is extended to 4,4'-bipyridyl N-oxide (BPNO), which initially gives a coordination polymer [Pb_2(NO_3)(NB)_3(BPNO)_2]_n which gets converted to another coordination polymer [Pb(NB)_2(BPNO)_2]_n. All these complexes are structurally characterized.