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Updated: May 20, 2026

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An asymmetric organocatalytic Povarov reaction with 2-hydroxystyrenes
Feng Shi1, Gui-Juan Xing, Zhong-Lin Tao
1School of Chemistry & Chemical Engineering, Jiangsu Normal University, Xuzhou, 221116, China.
Abstract:
An organocatalytic asymmetric three-component Povarov reaction involving 2-hydroxystyrenes has been established to provide an efficient method to access structurally diverse cis-disubstituted tetrahydroquinolines in high stereoselectivities of up to >99:1 dr and 97% ee. This protocol also provides an easy access to tetrahydroquinolines with chiral quaternary stereocenters upon using α-alkyl 2-hydroxystyrenes as substrates. The theoretical studies revealed that the Povarov reaction proceeded through a sequential vinylogous Mannich reaction and an intramolecular Friedel-Crafts reaction, wherein the phosphoric acid acted as bifunctional catalyst to activate 2-hydroxystyrene and aldimine simultaneously.
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