Bsi(OTf)3-mediated tandem annulation of 1-aryl isochroman-3-ones with oxygenated arenes: one-pot synthesis of polyoxygenated homotriptycenes.

Bi(OTf)3 (bismuth triflate)-mediated one-pot tandem annulation of oxygenated 1-aryl isochroman-3-ones with oxygenated arenes provides polyoxygenated homotriptycenes in moderate to good yields in MeNO2 at reflux (101 °C) for 10 h under an air atmosphere and easy-operational conditions via intermolecular and intramolecular Friedel-Crafts type procedures. A plausible mechanism is proposed and discussed. This protocol provides a highly effective ring-closure via three carbon-carbon (C-C) bond formations.

HCl-mediated cascade cyclocondensation of oxygenated arylacetic acids with arylaldehydes: one-pot synthesis of 1-arylisoquinolines.

In this paper, a concise, open-vessel synthesis of 1-arylisoquinolines is described via HCl-mediated intermolecular cyclocondensation of oxygenated arylacetic acids with arylaldehydes in the presence of NH2OH and alcoholic solvents under mild and one-pot reaction conditions. A plausible mechanism is proposed and discussed herein. In the overall reaction process, only water was generated as the byproduct. Various environmentally friendly reaction conditions are investigated for convenient transformation via the (4C + 1C + 1N) annulation. This protocol provides a highly effective ring closure via the formations of one carbon-carbon (C-C) bond, two carbon-nitrogen (C-N) bonds and one carbon-oxygen (C-O) bond.

Ac2O-Mediated Dearylacetylative Dimerization of 2-Arylacetyl-1-naphthols: Synthesis of Naphtho[1,2-b]furan-3-ones.

A novel and efficient route for the synthesis of 2-aryl-2-naphthyl naphtho[1,2-b]furan-3-ones is described via NaH/Ac2O-mediated dearylacetylative dimerization of 2-arylacetyl-1-naphthols in refluxing THF under open-flask conditions. A plausible mechanism is also proposed and discussed. Various reaction conditions are investigated for one-pot transformation.

Trifluoroacetic Anhydride Mediated One-Pot Synthesis of 1-Aryl Isochroman-3-ones via the Carboxy-Pictet-Spengler Reaction.

In this paper, a novel and open-vessel route for the facile-operational synthesis of 1-aryl isochroman-3-ones is described via (CF3CO)2O (trifluoroacetic anhydride, TFAA)-mediated intermolecular (4 + 2) annulation of oxygenated arylacetic acids with arylaldehydes or ketones under mild reaction conditions. A plausible mechanism is proposed and discussed herein. Various reaction conditions are investigated for efficient transformation under an environmentally friendly one-pot carboxy-Pictet-Spengler reaction.