Substrate-Controlled Aldol Reactions from Chiral α-Hydroxy Ketones

Abstract

Chiral α-hydroxy ketones are valuable platforms from which highly stereoselective substrate-controlled aldol reactions may be performed. The suitable choice of the hydroxyl protecting group and the enolization conditions produce aldol adducts that can be easily manipulated to give a variety of enantiomerically pure compounds. Moreover, such aldol reactions often play a crucial role in the coupling of elaborate fragments in advanced steps of the synthesis of natural products. Together, these features confer to the α-hydroxy ketones a prominent position among the chiral substrates that are capable of providing highly asymmetric transformations. 1 Introduction 2 Pioneering Contributions 3 Boron-Mediated Aldol Reactions from α-Hydroxy Ethyl Ketones 4 Titanium-Mediated Aldol Reactions from α-Hydroxy Ethyl Ketones 5 Other Aldol Reactions from α-Hydroxy Ethyl Ketones 6 Aldol Reactions from α-Hydroxy Methyl Ketones 7 Conclusions