title: Nickel-Catalyzed Aerobic Oxidative Isocyanide Insertion: Access to Benzimidazoquinazoline Derivatives via a Sequential Double Annulation Cascade (SDAC) Strategy.
abstract: An efficient protocol for the synthesis of quinazoline derivatives through nickel-catalyzed ligand-/base-free oxidative isocyanide insertion under aerobic conditions with intramolecular bis-amine nucleophiles has been developed. A one-pot sequential double annulation cascade (SDAC) strategy involving an opening of isatoic anhydride and annulation to benzimidazole and further nickel-catalyzed intramolecular isocyanide insertion has also been demonstrated. The method is operationally simple to implement with a wide variety of substrates and represents a new approach for multiple C-N bond formations. The methodology has been successfully applied to the syntheses of hitherto unreported imidazo-fused benzimidazoquinazolines via a deprotection-GBB reaction sequence. Further, a florescence study reveals the potential of the present strategy for the discovery of highly fluorescent probes.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Hyderabad (IITH) , Kandi, Sangareddy 502 285, Telangana, India.
authors.forename: Anand H
authors.initials: AH
authors.lastname: Shinde
authors.affiliation: Department of Chemistry, Indian Institute of Technology Hyderabad (IITH) , Kandi, Sangareddy 502 285, Telangana, India.
authors.forename: Sagar
authors.initials: S
authors.lastname: Arepally
authors.affiliation: Department of Chemistry, Indian Institute of Technology Hyderabad (IITH) , Kandi, Sangareddy 502 285, Telangana, India.
authors.forename: Mayur D
authors.initials: MD
authors.lastname: Baravkar
authors.affiliation: Department of Chemistry, Indian Institute of Technology Hyderabad (IITH) , Kandi, Sangareddy 502 285, Telangana, India.
authors.forename: Duddu S
authors.identifier: 0000-0001-5861-4126
authors.initials: DS
authors.lastname: Sharada