Synthesis of Polysubstituted Benzoic Esters from 1,2-Dihydropyridines and Its Application to the Synthesis of Fluorenones

Abstract

A convenient, instrumentally simple, and efficient methodology to transform 1,2-dihydropyridines into benzoic esters is described. The generated multisubstituted benzoic esters feature different topologies spanning from simple aromatic rings to fused benzocycloalkane systems. As an extension of this methodology, these benzoic esters are efficiently transformed into an array of fluorenone frameworks featuring interesting and novel topological patterns.

Intramolecular Acylation of Unactivated Pyridines or Arenes via Multiple C–H Functionalizations: Synthesis of All Four Azafluorenones and Fluorenones

“…Despite their diverse applications, the chemistry of azafluorenones has been least investigated. Among the various synthetic approaches reported for the synthesis of azafluorenones and fluorenones, intramolecular acylation reactions have been identified as a major contributor to the synthesis of these heterocycles. The classical Friedel–Crafts acylation approach to the synthesis of azafluorenones (and fluorenones) includes intramolecular acylation in 2-arylpyridines or biaryls containing an acyl source appropriately placed on one of the two rings (Scheme ).…”