Synthesis, reactions and structural features of monofluorinated cyclopropanecarboxylates
作者:Günter Haufe、Thomas C. Rosen、Oliver G.J. Meyer、R. Fröhlich、Kari Rissanen
DOI:10.1016/s0022-1139(02)00040-4
日期:2002.4
Monofluorinated cyclopropanecarboxylates are available in racemic or optically active form by transition metal-catalyzed reactions of vinylfluorides with diazoacetates. From α-fluorostyrene and tert-butyl diazoacetate in the presence of 2 mol% of an enantiopure bis(oxazoline) copper complex, a 81:19 mixture of tert-butyl trans- and cis-2-fluoro-2-phenylcyclopropanecarboxylates was obtained with high
通过氟乙烯与重氮乙酸酯的过渡金属催化反应,可以得到外消旋或旋光形式的单氟化环丙烷羧酸酯。从α氟苯乙烯和叔丁基重氮乙酸酯在2摩尔%的对映纯的双恶唑啉铜配合物存在下,的81:19混合物叔丁基反式-和顺用获得-2-氟-2- phenylcyclopropanecarboxylates对映体过量(ee)分别为93%或89%。相应的外消旋乙酯被用作合成顺式和反式羧酰胺的原料-抗抑郁药反式环丙胺类似物的异构体及其几种氟化的环丙基甲基和环丙基乙基胺。还合成了相应的对映体纯的环丙基甲醇及其一些衍生物。通过X射线晶体学检查选择了这些化合物的固态结构。特别是,顺式构型的氟化苯基环丙烷衍生物显示出非常紧密的分子间CH⋯FC接触。在(1S,2R)-(2-氟-2-苯基环丙基)甲醇的N-(4-溴苯基)氨基甲酸酯中发现了最短的这种距离(2.17A)。