Sydnone-based Approach to Hetero-helicenes Through 1,3-Dipolar-Cycloadditions

Expédite Yen-Pon (1) , Pier Alexandre Champagne (2) , Lucie Plougastel (1) , Sandra Gabillet (1) , Pierre Thuéry (3) , Mizuki Johnson (4) , Gilles Muller (4) , Grégory Pieters (1) , Frédéric Taran (1) , Kendall N Houk (2) , Davide Audisio (1)

1 SCBM - Service de Chimie Bio-Organique et de Marquage
2 CAL STATE LA - California State University [Los Angeles]
3 LCMCE - Laboratoire de Chimie Moléculaire et de Catalyse pour l'Energie (ex LCCEF)
4 SJSU - San Jose State University [San Jose]

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

Domains: Organic chemistry

Expédite Yen-Pon, Pier Alexandre Champagne, Lucie Plougastel, Sandra Gabillet, Pierre Thuéry, et al.. Sydnone-based Approach to Hetero-helicenes Through 1,3-Dipolar-Cycloadditions. Journal of the American Chemical Society, 2019, 141, pp.1435-1440. ⟨cea-01976854⟩