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Updated: Jun 12, 2026

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Organocatalytic enantioselective hydroxymethylation of oxindoles with paraformaldehyde as C1 unit
Xiong-Li Liu1, Yu-Hua Liao, Zhi-Jun Wu
1Key Laboratory for Asymmetric Synthesis & Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Beijing 100049, China.
Abstract:
A bifunctional thiourea-tertiary amine-catalyzed asymmetric hydroxymethylation of 3-substituted oxindoles using paraformaldehyde as the C1 unit was developed. A wide scope of oxindoles, bearing C3 sterically congested quaternary carbon centers, were smoothly obtained in good to excellent yields (up to 99%) and high enantioselectivities (up to 91% ee) under mild reaction conditions. A more significant feature of this approach employs cheap and readily available paraformaldehyde as a hydroxymethylation C1 unit, which is activated by chiral bifunctional thiourea organocatalysts.
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