Atroposelective [2+2+2] cycloadditions catalyzed by a rhodium(I)-chiral phosphate system

Mylène Augé (1) , Marion Barbazanges (1) , Anh Tuan Tran , Antoine Simonneau (1) , Paulin Elley , Hani Amouri (1) , Corinne Aubert (1) , Louis Fensterbank (1) , Vincent Gandon (2) , Max Malacria (1) , Jamal Moussa (1) , Cyril Ollivier (1)

1 IPCM - Institut Parisien de Chimie Moléculaire
2 ICSN - Institut de Chimie des Substances Naturelles

Enantioselective cationic Rh(I)-catalyzed [2+2+2] cycloaddition reactions between diynes and isocyanates relying on the chiral anion strategy have been devised. In the presence of [Rh(cod)Cl](2), 1,4-bis(diphenylphosphino)butane, and the silver phosphate salt Ag(S)-TRIP as the unique source of chirality, axially chiral pyridones were isolated with ees up to 82%. This approach is novel in the field of chiral anion-mediated asymmetric catalysis since atroposelective transformations have so far remained unprecedented. It also proves to be complementary to the classical strategy based on chiral L-type ligands.

Domaines: Chimie organique

Mylène Augé, Marion Barbazanges, Anh Tuan Tran, Antoine Simonneau, Paulin Elley, et al.. Atroposelective [2+2+2] cycloadditions catalyzed by a rhodium(I)-chiral phosphate system. Chemical Communications, 2013, 49 (71), pp.7833-7835. ⟨10.1039/c3cc43188f⟩. ⟨hal-01397612⟩