作者:Riku Shinohara、Hidehisa Kawashima、Narihito Ogawa、Yuichi Kobayashi
DOI:10.1016/j.tet.2019.03.050
日期:2019.5
Substitution of diethyl and diphenyl benzylic phosphates, Alk-CH(Ar1)OP(O)(OR)2 (R = Et, Ph; Alk = Me, Et, i-Pr; Ar1 = aryl), with the anions derived from Ar2CH2 (Ph2CH2,9H-xanthene and fluorene) and n-BuLi at –15 °C was studied. For phosphates with Me as an Alk, diethyl phosphates produced Me-CH(Ar1)CH(Ar2)2 (Ar1 = 4-halo-, 4-CN, 4-Me-, 2-Me, 2-Br-, 3-MeO-phenyl and 2-naphthyl). However, an unwanted
取代二乙基和二苯基苄基磷酸酯Alk-CH(Ar 1)OP(O)(OR)2(R = Et,Ph; Alk = Me,Et,i- Pr; Ar 1 =芳基),并衍生出阴离子选自Ar 2 CH 2(PH 2 CH 2,9 ħ呫吨和芴)和ñ正丁基锂在-15℃下进行了研究。对于以Me为碱的磷酸盐,磷酸二乙酯可制得Me-CH(Ar 1)CH(Ar 2)2(Ar 1 = 4-卤代,4-CN,4-Me-,2-Me,2-Br- ,3-MeO-苯基和2-萘基)。但是,在Et基团上的不需要的取代与Alk = Et-的磷酸盐竞争我-Pr。幸运的是,相应的磷酸二苯酯干净地进行了所需的取代。两种对映体富集的磷酸盐MeCH(Ph)OP(O)(OEt)2和EtCH(Ph)OP(O)(OPh)2进行了立体化学的完全转化。