骨架结构对大环主体化合物作为阴离子受体性能的影响

doi:10.6023/cjoc201402033

摘要/Abstract

通过文献报道的方法，高效合成了大环化合物环[2]（2，6-二（1H-咪唑基）吡啶[2]（1，4-二亚甲基苯）（1⁴⁺）和环[2]（2，6-二（1H-咪唑基）吡啶[2]（1，2-二亚甲基苯）（2⁴⁺）. 通过溶液中核磁¹H谱、气相电喷雾电离质谱（ESI-MS）及固相单晶衍射方法，详细考察了这两个大环主体化合物与一系列体积较小、形状各异的无机阴离子客体间的相互作用. Job's plot研究结果表明与2⁴⁺相比，大环主体1⁴⁺能够结合等量或者更多的阴离子客体；结合常数的计算表明，对于易于形成分子间氢键与大环主体进行复合的阴离子即Cl^-，，或，2⁴⁺与该类阴离子进行1：1复合的结合常数（K_a1）总是大于甚至是远大于1⁴⁺. 但是对于较难形成分子间氢键，随着离子半径的增大导致极化性增强，更易于发生anion-π作用的离子如Br^-和I^-，1⁴⁺与它们的结合常数近于甚至大于2⁴⁺. 推测产生上述现象的原因是由于2⁴⁺具有紧凑的骨架结构，使四个酸性较强的咪唑盐基2位C—H位点能够有效协同，与体积较小的阴离子同时形成强的分子间氢键；而1⁴⁺的骨架结构使得上述位点的空间距离较大，具有咪唑盐基团2位C—H键难以全部参与对阴离子的相互作用，而更易于同时与更多的阴离子结合，并更易于发生anion-π的协同作用. 上述结果展示了大环主体化合物的骨架结构将控制其空腔的大小、形状及与客体阴离子产生分子间氢键相互作用的C—H键位点的空间分布，从而极大地影响主客体之间复合的模式（如化学计量比和结合常数等）.

关键词: 大环化合物, 骨架结构, 弱相互作用, 阴离子复合

Two novel macrocycle hosts with flexible frameworks and cavities, cyclo[2](2,6-di(1H-imidazol-1-yl)pyridine)[2] (1,4-dimethylenebenzene) (1⁴⁺) and cyclo[2](2,6-di(1H-imidazol-1-yl)pyridine)[2](1,2-dimethylenebenzene) (2⁴⁺), were synthesized with high yields via cyclization reactions between 2,6-di(1H-imidazol-1-yl)pyridine and 1,4-bisbromomethyl benzene or 1,2-bisbromomethyl-benzene. Herein, the interactions between 1⁴⁺ or 2⁴⁺ and a series of inorganic anionic guests were studied in detail via the following methods: (1) ¹H NMR spectroscopy in d₆-DMSO solution; (2) electrospray ionization mass spectrometry (ESI-MS) in gas phase; (3) single crystal X-ray crystallography in solid state. It is noted that the anionic guest species has different shapes, namely anions with ball shapes like Cl^-, Br^-, I^-; linear anion N₃^-; triangle or tetrahedron HSO₄^-. The study found that 1⁴⁺ can bind more small inorganic anion species than macrocycle 2⁴⁺. In addition, the result implied that when the inorganic anion guest acts as strong intermolecular hydrogen bond acceptor (i.e. anionic guest (A^-) such as Cl^-, or ), the associate constant (K_a) maintains K_a[2⁴⁺·A^-]³⁺>K_a[1⁴⁺·A^-]³⁺; on the contrary, when anionic guest A^- (Br^- or I^-) is hard to form intermolecular hydrogen bonds but easy contribute to anion-π interaction, the association constants of the 1:1 (host:guest) complexes follow another trend (i.e. K_a[2⁴⁺·A^-]³⁺<K_a[1⁴⁺·A^-]³⁺ when A^- is Br^- or I^-). It is suggested that the skeleton of macrocycle host 2⁴⁺ well organize its four strong acidic imidazolium C—H bonds for effective small inorganic anion binding mainly via intermolecular hydrogen bonds; meanwhile the bigger cavity and longer distances between the strong acidic imidazolium C—H bonds of 1⁴⁺ leads two possible results: (1) worse cooperation of its acidic C—H bonds weaken the intermolecular hydrogen bonding interactions for small anion complexation; (2) its more relax backbone has possible benefits of binding more anion guests. In summary, small distinctions of the backbones between 1⁴⁺ and 2⁴⁺ result in significantly different anion complexations, including stoichiometries, association constants, binding modes, etc. This finding will help to guide following macrocyclic anion receptor design and study.

Key words: macrocycle, backbone, non-covalent weak interactions, anion binding

引用此文

魏金燕, 徐立进, 龚汉元. 骨架结构对大环主体化合物作为阴离子受体性能的影响[J]. 有机化学, 2014, 34(8): 1652-1661.

Wei Jinyan, Xu Lijin, Gong Hanyuan. Backbone Effect of Macrocycle Host Compound as Anion Receptor[J]. Chin. J. Org. Chem., 2014, 34(8): 1652-1661.

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参考文献

[1] Lehn, J. M.; Atwood, J. L.; Davies, L. E. Comprehensive Supramolecular Chemistry, Pergamon, New York, 1996, p. 27.
[2] Shen, J.-C. Supramolecular Layered Structures—Assembly and Functionalization, Science Press, Beijing, 2004, p. 1 (in Chinese).
(沈家骢, 超分子层状结构——组装与功能, 科学出版社, 北京, 2004, p. 1.)
[3] Liu, Y.; You, C.-C.; Zhang, H.-Y. Supramolecular Chemistry—Molecular Recognition and Assembly of Synthesized Receptors, Nankai University Press, Tianjin, 2001, p. 1 (in Chinese).
(刘育, 尤长城, 张衡益, 超分子化学——合成受体的分子识别与组装, 南开大学出版社, 天津, 2001, p. 1.)
[4] Lehn, J. M. Angew. Chem., Int. Ed. 1988, 27.
[5] Dodziuk, H. Introduction to Supramolecular Chemistry, Kluwer Academic Publishers, London, 2002.
[6] Lehn, J. M. Proc. Natl. Acad. Sci. 2002, 99, 4763.
[7] Steed, J. W.; Atwood, J. L. Supramol. Chem. 2006, 62.
[8] Levason, W.; Reid, G.; Ncleverty, J. A. Comprehensive Coordination Chemistry II, Pergamon, Oxford, 2004, p. 18.
[9] Prauzsch, V.; Ibach, S.; Vogtle, F. J. Inclusion Phenom. Macrocylic Chem. 1993, 33, 427.
[10] Gale, P. A. Chem. Commun. 2011, 47, 82.
[11] Sessler, J. L.; Gale, P. A.; Stoddart, J. F.; Cho, W. S. Anion Receptor Chemistry; Monographs in Supramolecular Chemistry, Royal Society of Chemistry, Cambridge, U. K., 2006.
[12] Wenzel, M.; Hiscock, J. R.; Gale, P. A. Chem. Soc. Rev. 2012, 41, 480.
[13] (a) Beer, P. D.; Gale, P. A. Angew. Chem., Int. Ed. 2001, 40, 486.
(b) Gong, H.-Y.; Xu, L.-J.; Zhou, L. Acta Chim. Sinica 2014, 72, 447 (in Chinese).
(龚汉元, 徐立进, 周丽, 化学学报, 2014, 72, 447.)
[14] (a) Ryo, S.; Li, W.; Kakuchi, T. Macromolecules 2011, 44, 4249.
(b) Zhang, D.-S.; Chen, J.-P.; Zeng, Y.; Yu, T.-J.; Li, Y. Chin. J. Org. Chem. 2013, 33, 110 (in Chinese).
(张读山, 陈金平, 曾毅, 于天君, 李嫕, 有机化学, 2013, 33, 110.)
[15] Lehn, J. M.; Hosseini, M. W.; Sessions, R. B. J. Am. Chem. Soc. 1981, 103, 1282.
[16] Lehn, J. M.; Hosseini, M. W. J. Am. Chem. Soc. 1987, 109, 7047.
[17] (a) Liu, G.; Shao, J. Acta Chim. Sinica 2011, 69, 1070 (in Chinese).
(刘阁, 邵杰, 化学学报, 2011, 69, 1070.)
(b) Li, Y.; Zhang, F.; Zou, L.-B.; Bao, X.-P. Chin. J. Org. Chem. 2013, 33, 2485 (in Chinese).
(刘勇, 张峰, 邹林波, 蹇军友, 鲍小平, 有机化学, 2013, 33, 2485.)
[18] Sessler, J. L.; Tomat, E. Acc. Chem. Res. 2007, 40, 371.
[19] Sessler, J. L.; Park, J. S.; Karnas, E.; Ohkubo, K. Science 2010, 329, 1324.
[20] Alcalde, E.; Dinares, I.; Mesquida, N. Top. Heterocycl. Chem. 2010, 24, 267.
[21] Willans, C. E.; Anderson, K. M.; Potts, L. C.; Steed, J. W. Org. Biomol. Chem. 2009, 7, 1500.
[22] Jiang, L.-S.; Yang, D.-K. Acta Chim. Sinica 2012, 70, 1385 (in Chinese).
(蒋腊生, 杨登科, 化学学报, 2012, 70, 1385.)
[23] Yoon, J.; Xu, Z.; Singh, N. J.; Sook, K.; Spring, D. R.; Kim, K. S. Chem. Eur. J. 2011, 17, 1163.
[24] Yoon, J.; Xu, Z.; Kim, S. K. Chem. Soc. Rev. 2010, 39, 1457.
[25] Yoon, J.; Kim, J. K.; Singh, N. J.; Kim, K. S. Chem. Soc. Rev. 2006, 35, 355.
[26] Ihm, H.; Yun, S.; Kim, H. G.; Kim, J. K.; Kim, K. S. Org. Lett. 2002, 4, 2897.
[27] Kim, S. K. Angew. Chem., Int. Ed. 2005, 44, 2899.
[28] Gao, G.; You, J.-S.; Zhou, H.-J. Chem. Commun. 2013, 49, 1832.
[29] You, J.-S.; Zhou, H.-J.; Gao, G. J. Am. Chem. Soc. 2013, 135, 14908.
[30] Hua, Y.; Flood, A. H. Chem. Soc. Rev. 2010, 39, 1262.
[31] Wei, T.-B.; Lin, Q.; Zhang, Y.-M. Sci. China, Ser. B 2004, 47, 295 (in Chinese).
(魏太保, 林奇, 张有明, 中国科学(B辑), 2004, 47, 295.)
[32] Sessler, J. L.; Cai, J. J.; Gong, H. Y.; Arambula, J. F., Hay, B. P. J. Am. Chem. Soc. 2010, 132, 14058.
[33] Wei, T.-b.; Zhang, Y.-M. Chin. J. Org. Chem. 2009, 29, 575 (in Chinese).
(魏太保, 张有明, 有机化学, 2009, 29, 575.)
[34] Wang, M.-X. Wang, D.-X. J. Am. Chem. Soc. 2013, 135, 892.
[35] Sessler, J. L.; Gong, H.-Y.; Rambo, B. M. Nat. Chem. 2010, 2, 406.
[36] Sessler, J. L.; Gong, H.-Y.; Rambo, B. M. J. Am. Chem. Soc. 2013, 135, 6330.
[37] Sessler, J. L.; Gong, H.-Y.; Rambo, B. M. J. Am. Chem. Soc. 2011, 133, 1526.
[38] Sessler, J. L.; Gong, H.-Y.; Rambo, B. M. Chem. Commun. 2011, 47, 5973.
[39] Oki, O. M. Applications of Dynamic NMR Spectroscopy to Organic Chemistry, VCH, Weinheim, 1985.
[40] Job, P. Ann. Chim. (Paris) 1928, 9, 113.
[41] Gans, P.; Sabatini, A.; Vacca, A. Talanta 1996, 43, 1739.