Catalytic Enantioselective Aza-Diels-Alder Reactions of Imines-An Approach to Optically Active Nonproteinogenicα-Amino Acids
作者:Sulan Yao、Steen Saaby、Rita G. Hazell、Karl Anker Jørgensen
DOI:10.1002/1521-3765(20000703)6:13<2435::aid-chem2435>3.0.co;2-z
日期:2000.7.3
well affording the corresponding aza-Diels-Alder product in high yield with up to 91% ee at room temperature. The present catalytic enantioselective reaction of imines provided an effective route to optically active nonproteinogenic alpha-amino acids. The products of the catalytic enantioselective aza-Diels-Alder reaction of the cyclic dienes can be used for the preparation of key compounds such as natural
已经开发了亚胺的催化对映选择性氮杂-Diels-Alder反应。在各种手性路易斯酸的存在下,已经研究了N-甲苯磺酰基α-亚氨基酯与包括活化,非活化,环状和无环二烯在内的不同二烯的反应。已经合成了一系列膦基-恶唑啉配体并评估了该反应。发现膦-恶唑啉配体与铜(I)盐的组合对于活化的二烯具有最佳结果,而BINAP-铜(I)配合物是所有研究的二烯的良好催化剂。对于活化的非环状二烯,可以以高于80%的分离产率和96%ee的价格获得aza-Diels-Alder产品,而对于未活化的环状二烯,exo非对映异构体是高达95%ee的主要产物。 。对于活化的环状共轭二烯2-三甲基甲硅烷氧基-1,3-环己二烯,该反应以曼尼希型加成反应进行,从而以良好的收率和高达96%的ee得到光学活性的γ-氧代α-氨基酸衍生物。未活化的无环二烯,2,3-二甲基-1,3-丁二烯与N-甲苯磺酰基α-亚氨基酯的反应生成的氮杂-Die