Homohelicity-enriched zinc bilinone dimers with chiral aliphatic spacers. Synthesis and application to chiral induction of a nematic liquid crystal
作者:Shigeyuki Yagi、Katsushi Hamakubo、Shigeru Ikawa、Hiroyuki Nakazumi、Tadashi Mizutani
DOI:10.1016/j.tet.2008.08.076
日期:2008.11
The zinc bilinone (ZnBL) dimers 4 and 5 bearing chiral aliphatic spacers ((2S,4S)-2,4-pentanedioxy and (3S,5S)-2,6-dimethyl-3,5-heptanedioxy for 4 and 5, respectively) were newly prepared, and their conformational distribution was investigated. The 1H NMR and circular dichroism spectra revealed that the present dimers predominantly adopted the homohelicity conformation (MM and PP for 4 and 5, respectively)
锌bilinone(ZnBL)二聚体4和5的轴承手性脂肪族间隔物((2小号,4小号)-2,4- pentanedioxy和(3小号,5小号)-2,6-二甲基-3,5- heptanedioxy为4和5分别)是新制备的,并对其构象分布进行了研究。的1 H NMR和圆二色性光谱显示本二聚体主要采用的构象homohelicity(MM和PP为4和5),尽管具有相应亚基结构的参考单体显示出较差的螺旋度富集。还研究了这些ZnBL二聚体对向列液晶(N-(4-甲氧基亚苄基)-4-丁基苯胺,MBBA)的螺旋扭曲能力。通过将二聚体掺入MBBA,可以实现高效的手性向列诱导。特别地,二聚物5表现出β中号的1800微米值-1。