Synthesis of substituted N-heterocycles via a cascade of Michael addition, double cyclization and air oxidation
Hunmoina Phukon1, Bikoshita Porashar1, Ankita Pradhan1
1Department of Chemistry, Indian Institute of Technology, Guwahati, 781039, Assam, India. asaikia@iitg.ac.in.
Abstract:
An efficient synthesis of α-carbolinones (pyridoindolones) and α-carbolines (pyridoindoles) from 2-(2-aminophenyl)acetonitriles and alkyl/arylidene malonates and 2-benzylidene-3-oxopentanoates mediated by Cs2CO3 in excellent yields has been developed. This methodology enables the formation of five- and six-membered nitrogen heterocyclic compounds via Michael addition, followed by double cyclization, elimination, rearrangement and air oxidation in a cascade fashion. Post-synthetic modification enables the synthesis of pentacyclic nitrogen heterocyclic compounds.
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