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Updated: May 14, 2025

Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Construction of Thiochroman-4-ols through a (4 + 2) Annulation Strategy Using Allenyl Sulfones as Substrates
Lilia Anani1, Jean-François Lohier2, Annie-Claude Gaumont1
1Univ Caen Normandie, ENSICAEN, Univ Rouen Normandie, INSA Rouen Normandie,CNRS, Institut CARMeN UMR 6064, F-14000 Caen, France.
Abstract:
Herein, we report an efficient and straightforward access to highly functionalized thiochroman-4-ol derivatives by the construction of S-C and C-C bonds in a domino fashion. The methodology is based on a (4 + 2) annulation reaction involving α-substituted allenyl sulfones and aromatic thiolates displaying an ortho α-ketoester group as substrates. The anionic sulfur species were generated in situ by reduction of the corresponding disulfides, using a Rongalite/K2CO3 system. The practicality of the strategy was further demonstrated by gram-scale synthesis, postmodifications, and compatibility with other types of electron-deficient allenes (allenoate and allenone).
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