Isothiourea-catalysed transfer hydrogenation of ?,?-unsaturated para-nitrophenyl esters
نویسندگان
چکیده
A protocol for the isothiourea-catalysed transfer hydrogenation of ?,?-unsaturated para-nitrophenyl esters using Hantzsch ester has been developed. Good to excellent yields are observed aryl bearing electron-withdrawing ?-substituents. The products can either be isolated directly in moderate (7 examples, 16–98%) or converted corresponding methyl (2 68–70% yield) benzyl amides 44–88% after situ reaction hydrogenated with appropriate nucleophile. Preliminary experiments showed that modest enantioinduction (76:24 er) is possible when a chiral isothiourea catalyst was used.
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ژورنال
عنوان ژورنال: Tetrahedron
سال: 2021
ISSN: ['0040-4020', '1464-5416']
DOI: https://doi.org/10.1016/j.tet.2020.131758