Synthesis of indole–cycloalkyl[b]pyridine hybrids via a four-component six-step tandem process

• Muthumani Muthu,
• Rakkappan Vishnu Priya,
• Abdulrahman I. Almansour,
• Raju Suresh Kumar and
• Raju Ranjith Kumar

Beilstein J. Org. Chem. 2018, 14, 2907–2915, doi:10.3762/bjoc.14.269

• condensation–nucleophilic addition to carbonyl–Michael addition–N-cyclization–elimination–air oxidation sequence to afford structurally intriguing indole–cycloalkyl[b]pyridine-3-carbonitrile hybrid heterocycles in excellent yields. Keywords: cycloalkyl[b]pyridine-3-carbonitrile; cyclododecanone; 3-(1H-indol-3

• -oxopropanenitriles, aromatic aldehydes, cycloalkanones and ammonium acetate. This work also stems from our continuous effort in synthesizing novel cycloalkyl[b]pyridine-3-carbonitrile hybrid heterocycles via tandem/domino reaction [71][72]. Results and Discussion Initially the precursors viz. 3-(1H-indol-3-yl)-3

• –cycloalkyl[b]pyridine-3-carbonitrile hybrid heterocycles have been achieved through a facile one-pot four-component strategy. This reaction occurred through a six-step tandem Hantzsch-like process involving Knoevenagel–Michael–nucleophilic addition–intramolecular cyclization–elimination–oxidative