Cyclobutane Formation by the Reaction of Ethenesulfonyl Fluoride with Dimethyl Diazomalonate

Li, Le; Mayer, Peter; Ofial, Armin R. and Mayr, Herbert (2022): Cyclobutane Formation by the Reaction of Ethenesulfonyl Fluoride with Dimethyl Diazomalonate. In: European Journal of Organic Chemistry, Vol. 2022, No. 39

Abstract

Attempts to synthesize fluorosulfonyl-substituted pyrazolines by Huisgen reactions (1,3-dipolar cycloadditions) of dimethyl diazomalonate with ethenesulfonyl fluoride led to the formation of dimethyl (2R*,3S*,4R*)-2-(1,3-dimethoxy-1,3-dioxopropan-2-yl)-3-(fluorosulfonyl)-4-((fluorosulfonyl)methyl)cyclobutane-1,1-dicarboxylate, a highly substituted cyclobutane derivative, which was characterized by NMR spectroscopy and single crystal X-ray crystallography. The mechanism of its formation was elucidated by carrying out the reaction at different temperatures and workup conditions. It is shown that an initial 1,3-dipolar cycloaddition yields a pyrazoline which extrudes nitrogen with formation of 1-fluorosulfonyl-2,2-bis(methoxycarbonyl)cyclopropane and dimethyl 2-(2-(fluorosulfonyl)ethylidene)malonate, the latter of which dimerized during chromatography on silica gel with formation of the isolated cyclobutane.

• Item Type: Journal article
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Subjects: 500 Science > 540 Chemistry
• ISSN: 1434-193X
• Language: English
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 491502892