|
|||||
|
|
gem-Difluorocyclopropane as core molecule candidate for liquid crystal compounds |
|
| Authors: | Toshiyuki Itoh Manabu Kanbara Shuichi Hayase Takashi Kato Yumiko Takagi |
| Institution: | a Department of Materials Science, Faculty of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan b Chisso Petrochemical Corporation, Goi Research Center, Research Laboratory I, 5-1 Goi-kaigan, Ichihara-shi, Chiba 290-8551, Japan c Department of Chemistry, Faculty of Education, Kagawa University, 1-1 Saiwai-cho, Taka-matsu 760-8522, Japan d Integrated Center for Sciences, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577, Japan |
| Abstract: | The synthesis of a novel chiral gem-difluorocyclopropane building block has been accomplished using chemo-enzymatic reaction protocol; the prochiral diol of 1,4-bis(2,2-difluoro-3-(hydroxymethyl)cyclopropyl)benzene (5) was converted to the corresponding chiral diacetate by Pseudomonas lipase (lipase SL-25, Meito)-catalyzed transesterification with vinyl acetate as acyl donor with >99% enantiomeric excess. Various types of diesters or dialkyl ether were prepared from the diol and their helical twisting power (HTP) was evaluated by addition of 1.0 wt% to a non-chiral nematic liquid crystal host; the HTP was significantly dependent on the structure of ester or ether moieties and diester of diol 5 with isopropylfumalic acid showed the largest HTP. |
| Keywords: | gem-Diflurocyclopropane Lipase-catalyzed reaction Enantiomerically pure Liquid crystal Chiral dopant Helical twisted power |
| 本文献已被 ScienceDirect 等数据库收录！ | |