三亞苯三碳烯之合成及配位聚合物之應用

Abstract

為了研究聚碳烯在有機金屬聚合物之應用，我們合成一系列以三亞苯為基底具有不同取代基的三咪唑鹽，在4b的情形下可以得到穩定的三碳烯；在4a的情形下可以透過硫脲證明三碳烯中間體的存在。三咪唑鹽可與銠金屬離子、碘化銅及醋酸銀生成三碳烯金屬錯合物。三硫脲可透過三氟酸酐氧化生成雙硫鍵而得到聚合物；三咪唑鹽可以配位銀或汞離子生成配位聚合物。

Recent development of poly-NHCs reveals their potential application in constructing organic and organometallic polymers. In order to contribute to the field, we synthesized a series of planar trisimidazolium salts, the apparent precursor for tris(NHC)s, based on the triphenylene backbone. These imidazolium salts with D3h symmetry are prepared in moderate yield with various bulky N-substituents. Among these imidazolium salts, the t-butyl substituted free carbene (4b) was generated via deprotonation of [4b-H3]3+ with LDA. For the diphenylmethyl substituted one, [4a-H3]3+, a tris-thiourea derivative (4a-S3) isolated from the reaction of [4a-H3]3+, K2CO3, and S8 suggests the generation of the free carbene intermediate. Compound 4a-S3 can be further converted into poly-cationic disulfide salt with triflic anhydride, which acts as an oxidizing agent for thioureas. Reactions of [4a-H3]3+ and Ag2O or Hg(OAc)2 yield the polymeric Ag-NHC polymer and Hg-NHC polymer, respectively.