Chen Qiu-Fang, Zhao Xin, Liu Quan, Jia Ji-Dong, Qiu Xiao-Ting, Song Ying-Lin, Young David James, Zhang Wen-Hua, Lang Jian-Ping
State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , Suzhou 215123, Jiangsu, People's Republic of China.
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , Shanghai 200032, People's Republic of China.
Inorg Chem. 2017 May 15;56(10):5669-5679. doi: 10.1021/acs.inorgchem.7b00261. Epub 2017 Apr 26.
Six analogous two-dimensional (2D) [TpWSCu]-based (Tp = hydridotris(3,5-dimethylpyrazol-1-yl)borate) networks, namely, {(Tp*WSCu)L} (2: L = 5-methyltetrazolate (Mtta); 3a: L = 5-ethyltetrazolate (Etta)) and {[(TpWSCu)L]BF} (3b: L = Etta; 4: L = 5-propyltetrazolate (Ptta); 5: L = 5-butyltetrazolate (Btta); 6: L = 5-pentyltetrazolate (Petta)) were synthesized by reactions of [EtN][TpWS] (1), [Cu(CHCN)]BF, NaN, and NHBF in different nitrile solvents (CH(CH)CN, n = 0, 1, 2, 3, and 4) under solvothermal conditions. In the structures of 2-6, each alkyl tetrazolate L as a bridging ligand was generated in situ from the "click" reaction between azide and nitrile. These 2D (6,3) networks support two types of voids wherein the pendant alkyl groups are accommodated. A tetrahedron cage-like cluster [TpW(μ-S)(μ-S')Cu] (7) was also formed in some of the above reactions and can be readily separated by solvent extraction. The proportion of 7 increased with the elongation of the alkyl chains and finally became the exclusive product when heptylnitrile was employed. Further use of CuCN as a surrogate for [Cu(CHCN)]BF with the aim of introducing additional CN bridges into the network led us to isolate a tetrazolate-free compound, {[EtN]{(TpWSCu)[Cu(CN)]}·2PhCHCN} (8·2PhCHCN), a unique 2D network that features {(TpWSCu)[Cu(CN)]}, {(TpWSCu)[Cu(CN)][Cu(CN)]}, and {(TpWSCu)[Cu(CN)]} ring subunits. Compounds 5-8 are soluble in DMF and exhibit a reverse saturable absorption and self-focusing third-order nonlinear optical (NLO) effect at 532 nm with hyperpolarizability γ values in the range of 4.43 × 10 to 5.40 × 10 esu, which are 400-500 times larger than that of their precursor 1. The results provide an interesting insight into the synergetic synthetic strategy related to the assembly of the [TpWSCu] cluster core, the "click" formation of the tetrazolate ligands, and the construction of the [Tp*WSCu] cluster-based 2D networks.
通过在溶剂热条件下，使[EtN][TpWS]（1）、[Cu(CHCN)]BF、NaN和NHBF在不同的腈类溶剂（CH(CH)CN，n = 0、1、2、3和4）中反应，合成了六个类似的基于二维（2D）[TpWSCu]（Tp* = 氢三（3,5 - 二甲基吡唑 - 1 - 基）硼酸酯）的网络，即{[(TpWSCu)L](μ - N)}（2：L = 5 - 甲基四唑（Mtta）；3a：L = 5 - 乙基四唑（Etta））和{[(TpWSCu)L]BF}（3b：L = Etta；4：L = 5 - 丙基四唑（Ptta）；5：L = 5 - 丁基四唑（Btta）；6：L = 5 - 戊基四唑（Petta））。在2 - 6的结构中，每个烷基四唑配体L是通过叠氮化物和腈之间的“点击”反应原位生成的桥连配体。这些二维（6,3）网络支持两种类型的空隙，其中悬垂的烷基基团被容纳。在上述一些反应中还形成了四面体笼状簇[TpW(μ - S)(μ - S')Cu]（7），并且可以通过溶剂萃取容易地分离出来。随着烷基链的延长，7的比例增加，当使用庚腈时最终成为唯一产物。进一步使用CuCN代替[Cu(CHCN)]BF以在网络中引入额外的CN桥，使我们分离出一种不含四唑的化合物{[EtN]{(TpWSCu)[Cu(CN)]}·2PhCHCN}（8·2PhCHCN），这是一种独特的二维网络，其特征在于{(TpWSCu)[Cu(CN)]}、{(TpWSCu)[Cu(CN)][Cu(CN)]}和{(TpWSCu)[Cu(CN)]}环亚基。化合物5 - 8可溶于DMF，并在532 nm处表现出反向饱和吸收和自聚焦三阶非线性光学（NLO）效应，超极化率γ值在4.43×10至5.40×10 esu范围内，比其前体1大400 - 500倍。这些结果为与[TpWSCu]簇核的组装、四唑配体的“点击”形成以及基于[Tp*WSCu]簇的二维网络的构建相关的协同合成策略提供了有趣的见解。
