Quan Liu^†‡§, Xin Zhao^†, Feng Zhou^∥, Ying-Lin Song^∥, Wen-Hua Zhang^*†（张文华）, and Jian-Ping Lang^*†‡（郎建平）

^† State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China

^‡ State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. China

^§ College of Chemistry and Chemical Engineering, Nantong University, Nantong 226019, P. R. China

^∥ School of Physical Science and Technology, Soochow University, Suzhou 215006, P. R. China

Cryst. Growth Des., 2016, 16 (6), pp 3206–3214

We have prepared a family of [WS₃Cu₂]-based coordination polymers with a rare μ-N type coordination by a simple one-pot assembly of [Et₄N][Tp*WS₃] (1) with CuCN in the presence of pyridine (py), 4,4′-bipyridine (bipy), 1,2-bis(4-pyridyl)ethane (bpea), and 2,4,6-tri(4-pyridyl)-1,3,5-triazine (tpt) at room temperature. The resulting coordination polymers [Tp*WS₃Cu₂(CN)(μ-py)]₂·py (2·py), [Tp*WS₃Cu₂(CN)₂Cu(μ-py)₂]₂·3py (3·3py), [Et₄N][{Tp*WS₃(CuCN)₂Cu}₂(CN)(μ₄-bipy)] (4), [Tp*WS₃Cu₂(CN)(μ₄-bpea)_0.5]₂·CH₂Cl₂ (5·CH₂Cl₂), and [Tp*WS₃Cu₂(CN)(μ₆-tpt)_1/3]₂ (6) share a butterfly-shaped [Tp*WS₃Cu₂] motif with sizable concave to accommodate pyridyl ligands. The approximate mirror symmetry of the motif also induces the orthogonal coalignment of the pyridyl ligands, reinforcing a unique μ-type association with the Cu centers of the cluster skeleton. Such a coordination mode, though scarce in general coordination chemistry, is universal in our series with good ligand tolerance including ligand size and symmetry. In addition, each butterfly-shaped [Tp*WS₃Cu₂] motif is linked by CN (2), Cu(CN)₂ (3), Cu₂(CN)₅/μ₄-bipy (4), CN/μ₄-bpea (5), and CN/μ₆-tpt (6) to yield diverse polydimensional structures showing one-dimensional zigzag chains (2 and 3), two-dimensional networks (4 and 5), and a three-dimensional net (6). The third-order nonlinear optical (NLO) property of 2–6 in DMF measured using a Z-scan technique at 532 nm demonstrated that 2–6 have a reverse saturable absorption and self-focusing effects with the hyperpolarizability γ values in the range of 6.32 × 10^–30 esu to 9.82 × 10^–30 esu. Such values are remarkably larger than that of their precursor complex 1 (1.07 × 10^–32 esu). The results provide an interesting insight into how the μ-type coordination mode of N-donor ligands affects the self-assembly of the [Tp*WS₃Cu₂]-supported coordination polymers and their structural topologies, as well as their third-order NLO performances.

链接：http://pubs.acs.org/doi/abs/10.1021/acs.cgd.6b00115