Metal-free annulative hydrosulfonation of propiolate esters: synthesis of 4-sulfonates of coumarins and butenolides. (24th February 2020)

• Record Type: Journal Article
• Authors: Fernandes, Rodney A.; Gangani, Ashvin J.; Kunkalkar, Rupesh A.
• Is Part Of: New journal of chemistry. Volume 44:Number 10(2020)
• Page Start: 3970
• Page End: 3984
• Publication Date: 2020-02-24
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c9nj06438a
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : An efficient metal-free and cost-effective method for the synthesis of coumarin and butenolide 4-sulfonates has been developed involving addition of sulfonic acids to ethyl propiolates followed by lactonization. Abstract : An efficient metal-free and cost-effective method for the synthesis of coumarin and butenolide 4-sulfonates (46 examples) has been developed. The reaction involves addition of sulfonic acids to ethyl propiolates followed by lactonization, resulting in direct formation of coumarin and butenolide 4-sulfonates. This methodology has been elaborated to Sonogashira and Suzuki coupling including the synthesis of rac -tolterodine.