Synthesis of enantiopure ethyl (1S,9aS)- and (1S,9aR)-1-phenyl-4,9-dioxohexahydropyrrolo[1,2-d][1,4]oxazepine-9a(7H)-carboxylate by carbenoid/ylide/Stevens-[1,2]-shift with ring enlargement
作者:Giorgio Chelucci、Antonio Saba、Raffaela Valenti、Alessia Bacchi
DOI:10.1016/s0957-4166(00)00312-8
日期:2000.8
pure ethyl (1S,9aS)- and (1S,9aR)-1-phenyl-4,9-dioxohexahydropyrrolo[1,2-d][1,4]oxazepine-9a(7H)-carboxylate were obtained by Cu(II)-catalyzed decomposition of an α-diazo carbonyl tethered to a chiral morpholinone. The reaction occurred with moderate diastereoselectivity but with complete enantioselectivity through the carbenoid/spiro-[5,6]-ammonium ylide/Stevens-[1,2]-shift with ring enlargement sequence
对映体纯净的(1 S,9a S)-和(1 S,9a R)-1-苯基-4,9-二氧六氢吡咯并[1,2- d ] [1,4]氧杂氮杂-9a (7 H)-羧酸乙酯通过Cu(II)催化将α-重氮羰基束缚在手性吗啉酮上进行分解得到。该反应以中等非对映选择性发生,但通过类胡萝卜素/螺-螺[5,6]-叶立德铵盐/史蒂文斯-[1,2]-移位(具有环扩大序列)而具有完全对映选择性。