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Sydnone-Based Approach to Heterohelicenes through 1,3-Dipolar-Cycloadditions.

ABSTRACT: The first approach to pyrazole-containing helicenes via sydnone-aryne [3 + 2]-cycloaddition is described. An unprecedented regioselectivity in the cycloaddition step toward the more sterically constrained product was observed in the presence of extended aromatic scaffolds. DFT calculations enabled understanding the origin of this unexpected selectivity.

SUBMITTER: Yen-Pon E

PROVIDER: S-EPMC7075354 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Sydnone-Based Approach to Heterohelicenes through 1,3-Dipolar-Cycloadditions.

Yen-Pon Expédite E Champagne Pier Alexandre PA Plougastel Lucie L Gabillet Sandra S Thuéry Pierre P Johnson Mizuki M Muller Gilles G Pieters Grégory G Taran Frédéric F Houk K N KN Audisio Davide D

Journal of the American Chemical Society 20190115 4

The first approach to pyrazole-containing helicenes via sydnone-aryne [3 + 2]-cycloaddition is described. An unprecedented regioselectivity in the cycloaddition step toward the more sterically constrained product was observed in the presence of extended aromatic scaffolds. DFT calculations enabled understanding the origin of this unexpected selectivity. ...[more]

PMID: 30628450

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