Stereoselective generation of cis-2-lithio-3-CF3-oxirane via CF3-substituted β-oxido carbenoids. Highly stereoselective synthesis of CF3-substituted tri- and tetrasubstituted oxiranes and tetrasubstituted alkenes
作者:Masaki Shimizu、Takuya Fujimoto、Xinyu Liu、Hiroshi Minezaki、Takeshi Hata、Tamejiro Hiyama
DOI:10.1016/j.tet.2003.09.098
日期:2003.12
1,1-trifluoropropan-2-ols with organolithium reagents R2Li in THF at −98°C stereoselectively produces 2,3-disubstituted 2-lithio-3-trifluoromethyloxiranes with Li and CF3cis. The reagents react with electrophiles El-X or organoboranes R3BR2 to give CF3-containing tri- and tetrasubstituted oxiranes or tetrasubstituted alkenes, respectively, with high diastereoselectivities.
在-98°C下用有机锂试剂R 2 Li在THF中处理2-取代的3,3-二氯-1,1,1-三氟丙烷-2-醇,立体选择性地生成2,3-二取代的2-lithio-3-trifluoromethyloxiranes Li和CF 3顺式。所述试剂与亲电试剂E1-X或有机硼烷R 3 BR 2反应,分别得到具有高非对映选择性的含CF 3的三和四取代的环氧乙烷或四取代的烯烃。