A Dipyrrin Programmed for Covalent Loading with Fullerenes. Issue 40 (19th June 2018)

• Record Type: Journal Article
• Authors: Li, Chengjie; Wurst, Klaus; Kräutler, Bernhard
• Is Part Of: Chemistry. Volume 24:Issue 40(2018)
• Page Start: 10032
• Page End: 10037
• Publication Date: 2018-06-19
• Subjects: C60-fullerene -- cheletropic reaction -- cycloaddition -- Diels–Alder reactions -- porphyrins; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201801995
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: We describe here a di‐(β, β′‐sulfoleno)pyrrin programmed for efficient and specific β, β′‐functionalization via [4+2] cycloaddition reactions. At 120 °C and in the presence of an excess of C60 ‐fullerene the di‐(β, β′‐sulfoleno)pyrrin decomposed cleanly, furnishing a di‐(β, β′‐fullereno)pyrrin and the corresponding monofullereno‐dipyrrin in an overall yield of 96 %. Hence, relatively mild thermolysis of the di‐(β, β′‐sulfoleno)pyrrin induced stepwise extrusion of two equivalents of SO2, producing highly reactive dipyrrin‐β, β′‐diene intermediates readily, providing a very effective path to [4+2]‐cycloadducts. As presented here by the example of the covalent attachment of C60 ‐fullerene units, a convenient general methodology for the efficient synthesis of covalent dipyrrin β, β′‐cycloadducts is made available. Abstract : A programmed dipyrrin : We report here a sulfolenodipyrrin that is programmed for efficient and specific β, β′‐functionalization via [4+2] cycloaddition. Thermolysis of the sulfolenodipyrrin induced the consecutive extrusion of two equivalents of SO2, giving highly reactive dipyrrin‐β, β′‐diene intermediates, ready for effective [4+2]‐cycloaddition. As shown by their covalent loading with two C60 ‐fullerene units, an efficient general methodology for the synthesis of dipyrrin β, β′‐cycloadducts is presented.