Chiral Rodlike Platinum Complexes, Double Helical Chains, and Potential Asymmetric Hydrogenation Ligand Based on “Linear” Building Blocks: 1,8,9,16-Tetrahydroxytetraphenylene and 1,8,9,16-Tetrakis(diphenylphosphino)tetraphenylene
作者:Hai-Yan Peng、Chi-Keung Lam、Thomas C. W. Mak、Zongwei Cai、Wai-Tang Ma、Yu-Xue Li、Henry N. C. Wong
DOI:10.1021/ja051013l
日期:2005.7.1
afford highly ordered structures. A 1:1 adduct of 4,4'-bipyridyl and (+/-)-3a exists in a dimeric form of 3a linked by 4,4'-bipyridyl through hydrogen bonds. Pyrazine serves as a short linker between achiral parallel chains each formed by (+/-)-3a, while self-assembly of homochiral 3a into alternate parallel chains occurs in the adduct of 5,5'-dipyrimidine with (+/-)-3a. Self-assembly of (S,S)-3a or (R
本文涉及通过铜 (II) 介导的氧化偶联合成 1,8,9,16-四羟基四亚苯基 (3a),将其拆分为光学对映体,并将其转化为 1,8,9,16-四(二苯基膦基)四亚苯基(3b)。在这些手性“线性”构件的基础上,三个棒状手性配合物,三嵌段(R,R,R,R)-17和(S,S,S,S)-20和五嵌段(R,R,R, R,R,R,R,R)-22, 被构建。作为氢键供体,外消旋和光学活性 3a 可以与线性受体组装以提供高度有序的结构。4,4'-联吡啶和 (+/-)-3a 的 1:1 加合物以 3a 的二聚形式存在,由 4,4'-联吡啶通过氢键连接。吡嗪充当每个由 (+/-)-3a 形成的非手性平行链之间的短接头,而同手性 3a 自组装成交替平行链发生在 5,5'-二嘧啶与 (+/-)-3a 的加合物中。(S,S)-3a 或 (R,R)-3a 与 4,4'-联吡啶的自组装产生了由手性四醇 3a 分子形成的手性双螺旋链的堆积。衍生自