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Intramolecular aminocyanation of alkenes by N-CN bond cleavage.

ABSTRACT: A metal-free, Lewis acid promoted intramolecular aminocyanation of alkenes was developed. B(C6F5)3 activates N-sulfonyl cyanamides, thus leading to a formal cleavage of the N-CN bonds in conjunction with vicinal addition of sulfonamide and nitrile groups across an alkene. This method enables atom-economical access to indolines and tetrahydroquinolines in excellent yields, and provides a complementary strategy for regioselective alkene difunctionalizations with sulfonamide and nitrile groups. Labeling experiments with (13)C suggest a fully intramolecular cyclization pattern due to the lack of label scrambling in double crossover experiments. Catalysis with Lewis acid is realized and the reaction can be conducted under air.

SUBMITTER: Pan Z

PROVIDER: S-EPMC4077192 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Intramolecular aminocyanation of alkenes by N-CN bond cleavage.

Pan Zhongda Z Pound Sarah M SM Rondla Naveen R NR Douglas Christopher J CJ

Angewandte Chemie (International ed. in English) 20140409 20

A metal-free, Lewis acid promoted intramolecular aminocyanation of alkenes was developed. B(C6F5)3 activates N-sulfonyl cyanamides, thus leading to a formal cleavage of the N-CN bonds in conjunction with vicinal addition of sulfonamide and nitrile groups across an alkene. This method enables atom-economical access to indolines and tetrahydroquinolines in excellent yields, and provides a complementary strategy for regioselective alkene difunctionalizations with sulfonamide and nitrile groups. Lab ...[more]

PMID: 24719371

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