Structural Transformations of Pb(II)-trans-1,2-bis(4鈥?pyridyl)ethene Coordination Polymers in Solution
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- 作者：Abdul Malik Puthan Peedikakkal ; Jagadese J. Vittal
- 刊名：Crystal Growth & Design
- 出版年：2011
- 出版时间：October 5, 2011
- 年：2011
- 卷：11
- 期：10
- 页码：4697-4703
- 全文大小：968K
- 年卷期：v.11,no.10(October 5, 2011)
- ISSN：1528-7505
文摘
Reaction of bpe (bpe = trans-1,2-bis(4鈥?pyridyl)ethylene) with Pb(OAc)2路3H2O in the presence of trifluoroacetic acid (HTFA) affords a triple-stranded coordination polymer (CP) [Pb3(渭-bpe)3(渭-O2CCF3)2(渭-O2CCH3)2(O2CCF3)2] (1) in two days, which undergoes structural transformation in solution to yield a two-dimensional (2D) sheet-like CP [Pb(渭-bpe)(渭-O2CCH3)(O2CCF3)]路0.25bpe路1.75H2O (2) in three weeks; finally compound 2 rearranges to [Pb(渭-bpe)(O2CCH3)(O2CCF3)] (3) in the fourth week. Compound 3 has a molecular fabric-like interwoven structure formed by spiral one-dimensional (1D) coordination polymeric chains. Reaction of bpe with Pb(O2CCF3)2 and Pb(OAc)2路3H2O respectively in equimolar ratio produces [Pb(渭-bpe)(渭-O2CCF3)2] (4) and [Pb(渭-bpe)(O2CCH3)2]路0.25H2O (5). The compound 4 is a three-dimensional (3D) CP with a 42.63.8-sra (SrAl2) topology, whereas 5 has a double-stranded structure with Pb(II)路路路蟺 (pyridyl) interactions between 1D chains. The compounds [Pb(渭-bpe)(渭-O2CCH3)(O2CCF3)]路0.25bpe (2a), 4, and 5 have been characterized by X-ray crystallography, while 1 and 3 were reported before. The factors influencing the rearrangement of CPs in solution have been discussed. The structural topological features observed in 2a, 4, and 5 have been attributed to the coordination preference of the Pb(II) and the carboxylate ligands.