Synthesis, X-ray crystallographic, and dynamic 1H NMR studies of crown-tetrathia[3.3.3.3]metacyclophanes—conformational control by cooperative intramolecular C–H⋯π interaction both in solid state and in solution
作者:Jian-Wei Xu、Wei-Ling Wang、Yee-Hing Lai
DOI:10.1016/j.tet.2005.07.071
日期:2005.9
Crown-tetrathia[3.3.3.3]metacyclophanes 3a–c were synthesized via intermolcular coupling reaction in 22–30% yields. X-ray crystal analysis of 3b revealed that it adopted a perpendicular conformation (3b-B or 3b-C) in which two aromatic rings were inclined to be perpendicular to the opposite aromatic rings, driving two internal methyl groups into the π-cloud of the corresponding benzene rings. Furthermore