Enantioselective Access to Triaryl-2-pyrones with Monoaxial or Contiguous C–C Diaxes via Oxidative NHC Catalysis
Si-Chen Zhang, Shengping Liu, Xia Wang, Shaojie Wang, Hui Yang, Lin Li, Bin‐Miao Yang, Ming Wah Wong, Yu Zhao, Shenci Lu
Abstract
We present herein an unprecedented stereoselective synthesis of triaryl-2-pyrones with monoaxial or contiguous diaxes from readily available starting materials. This N-heterocyclic carbene catalysis method adopts an atroposelective annulation of 2-aryketones with ynals under oxidative conditions. The annulation includes the construction of one or two axes in a single operation, achieves step economy, and affords axially chiral triaryl-2-pyrones in moderate to good yields, with high to excellent enantioselectivities. DFT calculations of the relative energies of stereoisomers and rotational barriers were performed.
Topics & Concepts
AnnulationCarbeneCatalysisEnantioselective synthesisChemistryOxidative phosphorylationStereoselectivityCombinatorial chemistryOrganic chemistryBiochemistryAxial and Atropisomeric Chirality SynthesisN-Heterocyclic Carbenes in Organic and Inorganic ChemistrySynthesis and Properties of Aromatic Compounds