On the scope of diastereoselective epoxidation of various chiral auxiliaries derived enones: the conformational analysis of camphor derived N- and O-enones
作者:Wei-Der Lee、Ching-Chen Chiu、Hua-Lin Hsu、Kwunmin Chen
DOI:10.1016/j.tet.2004.05.095
日期:2004.7
Various camphor derived N- and O-enones were treated with selected oxidants to provide the corresponding epoxides in a wide range of diastereoselectivity. For camphorsultam derived activated alkenes, high to excellent stereoselectivities were obtained when the s-trans enones were treated with methyl(trifluoromethyl)dioxirane. On the other hand, for exo-10,10-diphenyl-2,10-camphanediol (3) and exo-10
用选定的氧化剂处理各种樟脑衍生的N-和O-烯酮,可在很宽的非对映选择性范围内提供相应的环氧化物。对于樟脑素衍生的活化烯烃,当用甲基(三氟甲基)二环氧乙烷处理s-反式烯酮时,可获得高至优异的立体选择性。另一方面,对于exo -10,10-diphenyl-2,10-camphanediol(3)和exo -10,10-diphenyl-10-methoxy-camphaneol(4)衍生的烯烃,使用s-cis在相同的反应条件下,烯酮得到所需的环氧化物,具有极好的非对映选择性。立体选择性高度依赖于助剂衍生的烯酮的几何形状,并讨论了立体化学诱导。