Isothiourea-catalyzed transfer hydrogenation of α,β-unsaturated para-nitrophenyl esters
Abstract
A protocol for the isothiourea-catalysed transfer hydrogenation of α,β-unsaturated para-nitrophenyl esters using Hantzsch ester has been developed. Good to excellent yields are observed using α,β-unsaturated aryl esters bearing electron-withdrawing β-substituents. The aryl ester products can either be isolated directly in moderate to excellent yields (7 examples, 16–98%) or converted to the corresponding methyl esters (2 examples, 68–70% yield) or benzyl amides (2 examples, 44–88% yield) after in situ reaction of the hydrogenated ester with the appropriate nucleophile. Preliminary experiments showed that modest enantioinduction (76:24 er) is possible when a chiral isothiourea catalyst was used.
Citation
Wu , J , Young , C M & Smith , A D 2020 , ' Isothiourea-catalyzed transfer hydrogenation of α,β-unsaturated para -nitrophenyl esters ' , Tetrahedron , vol. In press , 131758 . https://doi.org/10.1016/j.tet.2020.131758
Publication
Tetrahedron
Status
Peer reviewed
ISSN
0040-4020Type
Journal article
Description
The research leading to these results (JW) has received funding from the ERC under the European Union's Seventh Framework Programme (FP7/2007–2013)/ERC grant agreement no 279850. ADS thanks the Royal Society for a Wolfson Research Merit Award.Collections
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