Base‐Induced Cyclization of Propargyl ­Alkenylsulfones: A High‐Yielding Synthesis of 4, 5‐Disubstituted 2H‐Thiopyran 1, 1‐Dioxides. Issue 27 (14th August 2015)

• Record Type: Journal Article
• Authors: Hatial, Ishita; Das, Joyee; Ghosh, Ananta K.; Basak, Amit
• Is Part Of: European journal of organic chemistry. Issue 27(2015)
• Page Start: 6017
• Page End: 6024
• Publication Date: 2015-08-14
• Subjects: Sulfur heterocycles -- Cycliza­tion -- Electrocyclic reactions -- Alkynes -- ­Allylic compounds; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201500633
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: A convenient synthesis of 4, 5‐disubstituted 2 H ‐thiopyran 1, 1‐dioxides is reported through a base induced process starting from eneyne sulfones. Except for strongly electron‐withdrawing groups, the reaction tolerated a wide variety of substituents in the two aryl rings. This finding represents a major departure from the behaviour of the corresponding ethers. The reaction most probably proceeds through a 6π‐electrocyclization from an in‐situ‐generated 1, 3, 5‐trienyl sulfinate. Abstract : The base‐induced cyclization of eneynesulfones to give 2 H ‐thiopyran 1, 1‐dioxides is described.