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A Dipyrrin Programmed for Covalent Loading with Fullerenes.

ABSTRACT: We describe here a di-(?,?'-sulfoleno)pyrrin programmed for efficient and specific ?,?'-functionalization via [4+2] cycloaddition reactions. At 120?°C and in the presence of an excess of C60 -fullerene the di-(?,?'-sulfoleno)pyrrin decomposed cleanly, furnishing a di-(?,?'-fullereno)pyrrin and the corresponding monofullereno-dipyrrin in an overall yield of 96?%. Hence, relatively mild thermolysis of the di-(?,?'-sulfoleno)pyrrin induced stepwise extrusion of two equivalents of SO2 , producing highly reactive dipyrrin-?,?'-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 ?,?'-cycloadducts is made available.

SUBMITTER: Li C

PROVIDER: S-EPMC6099335 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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A Dipyrrin Programmed for Covalent Loading with Fullerenes.

Li Chengjie C Wurst Klaus K Kräutler Bernhard B

Chemistry (Weinheim an der Bergstrasse, Germany) 20180619 40

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 C<sub>60</sub> -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 SO<sub> ...[more]

PMID: 29802661

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