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Organocatalytic asymmetric transformations of modified Morita-Baylis-Hillman adducts
Tian-Yu Liu1, Min Xie, Ying-Chun Chen
1Department of Medicinal Chemistry, College of Pharmacy, The Third Military Medical University, Chongqing 400038, China.
Abstract:
Chiral Lewis basic tertiary amines or phosphines can enable properly modified Morita-Baylis-Hillman (MBH) adducts to undergo asymmetric allylic substitutions with a wide range of nucleophiles. In addition, assisted by a Brønsted base, chiral Lewis bases can also catalytically convert modified MBH adducts into allylic ylides, which can be engaged in a variety of asymmetric annulation reactions. This tutorial review will focus on such chiral Lewis base-catalysed asymmetric transformations of MBH adducts, especially those developed over the past five years, allowing for the rapid construction of densely functionalised chiral molecules with high levels of regio- and stereoselectivities.
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