Efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates: A concise synthesis of difluoromethylene-containing 1,4-thiazine derivatives

A practical method for the construction of difluoromethylene-containing 1,4-thiazine moieties using readily available diethyl bromodifluoromethanephosphonate (BrCF2 PO(OEt)2 ) as difluorocarbene precusor has been developed. This transformation features the efficient capture of difluorocarbene by pyridinium 1,4zwitterionic thiolates. A series of structurally novel and functionalized difluoromethylene-containing 1,4thiazine derivatives were thus synthesized in good yields. (c) 2024 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.