Asymmetric Michael Addition of a Recyclable Chiral Amine: Inversion of Stereoselectivity Caused by the Difference of Ethereal Solvents
作者:Manabu Node、Daisuke Hashimoto、Takahiro Katoh、Shunsuke Ochi、Minoru Ozeki、Tsunefumi Watanabe、Tetsuya Kajimoto
DOI:10.1021/ol8007793
日期:2008.7.3
The Michael addition of a chiral amine [(-)- 6] to alpha,beta-unsaturated esters ( 4) was attained and the stereoselectivity was inverted by changing the solvent from diethyl ether to tetrahydrofuran when alpha,beta-unsaturated esters having an aromatic ring at the beta-position were employed. In addition, the chiral auxiliary in the Michael adducts ( 9A) was facilely removed with N-iodosuccinimide
当α,β-不饱和酯具有芳族化合物时,通过手性胺[(-)-6]的迈克尔加成到α,β-不饱和酯(4)上,并通过将溶剂从乙醚改为四氢呋喃来反转立体选择性。使用在β位的环。此外,用N-碘代琥珀酰亚胺轻松除去了迈克尔加合物(9A)中的手性助剂,得到了β-氨基酯(10A)和2-甲氧基-d-冰片醛(11),可以将其回收为手性胺( 6)通过还原胺化。