Enantioselective [3+2]-cycloadditions catalyzed by a protected, multifunctional phosphine-containing α-amino acid
Enantioselective [3+2]-cycloadditions catalyzed by a protected, multifunctional phosphine-containing α-amino acid
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DOI：
10.1021/ja0734243
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发表时间：
2007-09-12
影响因子：
15
通讯作者：
Miller, Scott J.
中科院分区：
文献类型：
--
作者：
Cowen, Bryan J.;Miller, Scott J.
报道了CC-丙二烯酯与烯酮的催化不对称[3 + 2]-环加成反应。我们已经发现，简单的含膦保护的（X）-氨基酸衍生物能够以高收率促进这样的环加成，具有显著水平的区域选择性和对映选择性。此外，在与查耳酮底物的环加成中使用手性外消旋γ-取代的联烯酸酯导致“去外消旋化”反应，从而以高达93%ee的高产率提供环戊烯。
Catalytic asymmetric [3 + 2]-cycloaddition reactions between CC-allenic esters and enones are presented. We have found that a simple phosphine-containing protected (X-amino acid derivative is capable of promoting such cycloadditions in high yields with significant levels of regioselectivity and enantioselectivity. Furthermore, employing chiral racemic gamma-substituted allenoates in the cycloaddition with chalcone substrates results in a "deracemization" reaction furnishing cyclopentenes in high yields with up to 93% ee.