The Enantioselectivity and the Stereochemical Course of Copper-Catalyzed Intramolecular CH Insertions of Phenyliodonium Ylides
作者:Paul Müller、Christelle Boléa
DOI:10.1002/1522-2675(200202)85:2<483::aid-hlca483>3.0.co;2-q
日期:2002.2
CH insertion of phenyliodonium ylide 1b was investigated at 0° in the presence of several chiral ligands. Enantioselectivities varied in the range 38–72%, and were higher than those resulting from reaction of the diazo compound 1c at 65°. The intramolecular insertion of the enantiomerically pure methyl diazoacetate (R)-20 and of the corresponding phenyliodonium ylide (R)-21 proceeded to (R)-23 with
在存在几个手性配体的情况下,在 0° 研究了 Cu 催化的苯碘鎓叶立德 1b 的分子内 CH 插入。对映选择性在 38-72% 范围内变化,高于重氮化合物 1c 在 65° 反应产生的对映选择性。对映体纯的重氮乙酸甲酯 (R)-20 和相应的苯基碘叶立德 (R)-21 的分子内插入进行到 (R)-23 并保留 [Cu(hfa)2] 的构型 (hfa=六氟乙酰丙酮=1 ,1,1,5,5,5-六氟戊烷-2,4-二酮)和[Rh2(OAc)4]。这些结果与铜催化的苯碘鎓叶立德插入的卡宾机制一致。然而,