Synthesis of 2-Amino-2′-hydroxy-1,1′-biaryls via Cascade Benzannulation and C–N Bond Cleavage Sequence
Raju Adepu, Jadhav Rahul Dhanaji, Polasani Samatha, Prathama S. Mainkar, S. Chandrasekhar
Abstract
A serendipitous synthesis of N-substituted 2-amino-2'-hydroxy-1,1'-biaryls through an aryne annulation with indolyl β-ketonitrile/ester in a cascade manner is demonstrated. The reaction sequence involves benzyne-mediated [2 + 2] Stoltz-type cycloaddition-cleavage and intramolecular Michael addition followed by C-N bond cleavage under transition-metal-free reaction conditions. Interestingly, while [4 + 2] Diels-Alder reaction is a possible pathway, no traces of the regioisomer was isolated.
Topics & Concepts
AryneChemistryIntramolecular forceAnnulationCleavage (geology)CycloadditionBond cleavageStereochemistryCascade reactionCascadeSequence (biology)Combinatorial chemistryMedicinal chemistryCatalysisOrganic chemistryFracture (geology)Geotechnical engineeringChromatographyBiochemistryEngineeringCyclization and Aryne ChemistryCatalytic Alkyne ReactionsChemical synthesis and alkaloids