Isothiourea-catalyzed enantioselective Michael addition of malonates to α,β-unsaturated aryl esters
Abstract
An enantioselective Michael addition of malonates to α,β-unsaturated para-nitrophenyl esters was achieved using the Lewis basic isothiourea HyperBTM, giving excellent levels of product enantioselectivity (up to >99:1 enantiomeric ratio) in good yields and with complete regioselectivity (>20:1 regioselectivity ratio) in the presence of alternative (phenyl ketone and ethyl ester) Michael acceptors. Density functional theory calculations indicate that N-acylation is rate-limiting. This constitutes a rare example of a highly enantioselective addition of simple, readily available malonates to α,β-unsaturated esters.
Citation
Wu , J , Young , C M , Watts , A A , Slawin , A M Z , Boyce , G , Buehl , M & Smith , A D 2022 , ' Isothiourea-catalyzed enantioselective Michael addition of malonates to α,β-unsaturated aryl esters ' , Organic Letters , vol. 24 , no. 22 , pp. 4040-4045 . https://doi.org/10.1021/acs.orglett.2c01486
Publication
Organic Letters
Status
Peer reviewed
ISSN
1523-7060Type
Journal article
Rights
Copyright © 2022 The Authors. Open Access article Licensed under Creative Commons Attribution CC-BY 4.0.
Description
MB thanks EaStCHEM and the School of Chemistry for support.Collections
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