Inverse electron demand asymmetric cycloadditions of cyclic carbonyl ylides catalyzed by chiral Lewis acids—Scope and limitations of diazo and olefinic substrates
作者:Hiroyuki Suga、Satoshi Higuchi、Motoo Ohtsuka、Daisuke Ishimoto、Tadashi Arikawa、Yuta Hashimoto、Shunta Misawa、Teruko Tsuchida、Akikazu Kakehi、Toshihide Baba
DOI:10.1016/j.tet.2010.01.095
日期:2010.4
enantioselectivities (73–97% ee) were also obtained for the cycloadditions between 3-acyl-2-benzopyrylium-4-olates, generated from methyl 2-(2-diazo-1,3-dioxoalkyl)benzoates and butyl or cyclohexyl vinyl ethers, in the presence of binaphthyldiimine (BINIM)–Ni(II) complexes (10 mol %). Under similar conditions, the reaction between methyl 2-(2-diazo-1,3-dioxohexyl)benzoate and 2,3-dihydrofuran was highly
通过Rh 2(OAc)4催化邻甲氧基羰基分解生成的环己基乙烯基醚与2-苯并吡啶-4-醇酸酯之间的反电子需求的1,3-偶极环加成反应,获得了高对映选择性(94-96%ee)-α-重氮苯乙酮。该反应有效地催化的Eu(OTF)3,何(OTF)3,或Gd(OTF)3种性2,6-二复合物(10摩尔%)[(4-小号,5小号)-4,5-二苯基-2-恶唑啉基]吡啶。与其他富电子偶极亲子的反应,例如烯丙醇,2,3-二氢呋喃和丁基叔丁基丁基二甲基甲硅烷基乙烯酮缩醛显示中等的对映体选择性(60-73%ee)。还获得了由2-(2-重氮-1,3-二氧代烷基)苯甲酸甲酯和丁酯生成的3-酰基-2-苯并吡啶-4-醇酸酯之间的环加成反应,具有良好的对映选择性(73-97%ee)。环己基乙烯基醚,在联萘胺(BINIM)-Ni(II)络合物(10摩尔%)的存在下。在类似条件下,2-(2-重氮基-1,3- dioxohexyl)苯甲酸乙酯和2