标题：Facile Synthesis of Enantiomerically Pure 1-(5-Bromo-2-chlorophenyl)-1-(4-ethoxyphenyl)ethane
作者：Zhang Shuo; Wang Wenjin; Li Chuan; Liu Peng; Xu Weiren; Tang Lida; Wang Jianwu; Zhao Guilong
作者机构：[Zhang, S] School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China, Tianjin Key Laboratory of Molecular Design and Dru 更多
通讯作者地址：[Wang, JW]Shandong Univ, Sch Chem & Chem Engn, Jinan 250100, Peoples R China.
摘要：A facile 7-step procedure for the synthesis of enantiomerically pure 1-(5-bromo-2-chlorophenyl)-1-(4ethoxyphenyl)ethanes[(R)-2 and(S)-2] that started from (5-bromo-2-chlorophenyl)(4-ethoxyphenyl)methanone 3 was developed. The key step was the resolution of 2-(5-bromo-2-chlorophenyl)-2-(4-ethoxyphenyl)acetic acid 6 by crystallizations of its L- and D-menthyl esters 7 and 8 from petroleum ether to give optically pure enantiomers 9 and 10, respectively. The absolute configurations of the products were unambiguously determined by single-crystal X-ray diffractions of four key intermediates, 9, 10, 13 and 14. This procedure is characterized by inexpensiveness, scalability and ability to produce two individual enantiomers of a diarylethane with unambiguously determined absolute configurations and high enantiomeric purities.