Divergent Synthesis of 1,2-Benzo[ e ]thiazine and Benzo[ d ]thiazole Analogues Containing a S -Trifluoromethyl Sulfoximine Group: Preparation and New Properties of the Adachi Reagent

Anne-Laure Barthelemy (1) , Elsa Anselmi (1) , Thanh-Nghi Le (2) , Giang Vo-Thanh (2) , Régis Guillot (2) , Karinne Miqueu (3) , Emmanuel Magnier (1)

1 ILV - Institut Lavoisier de Versailles
2 ICMMO - Institut de Chimie Moléculaire et des Matériaux d'Orsay
3 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux

We report here the preparation of unprecedented analogues of 1,2-benzothiazine and benzoisothiazoleincorporating theS-trifluoromethyl sulfoximine group in their core. Using a stable precursor to start, cyclization occurs via acatalytic controlled process. The choice of the catalyst is crucial for selectivity toward thefive- or the six-membered ring.Interestingly, one of the benzothiazines can be converted on a gram scale into the trifluoromethylating Adachi reagent. We alsodisclose thefirst use of this reagent as a source of radical CF3under photoredox catalysis. DFT calculations were performed toclarify the cyclization mechanism.

Domaines: Chimie théorique et/ou physique; Chimie analytique; Chimie organique

Anne-Laure Barthelemy, Elsa Anselmi, Thanh-Nghi Le, Giang Vo-Thanh, Régis Guillot, et al.. Divergent Synthesis of 1,2-Benzo[ e ]thiazine and Benzo[ d ]thiazole Analogues Containing a S -Trifluoromethyl Sulfoximine Group: Preparation and New Properties of the Adachi Reagent. Journal of Organic Chemistry, 2019, 84 (7), pp.4086-4094. ⟨10.1021/acs.joc.9b00079⟩. ⟨hal-02093608⟩