Synthesis of 2‐Aminoquinazoline‐ and 2‐Aminopyrimidine‐Fused Hybrid Scaffolds by Copper‐Catalyzed C(sp2)–N Coupling and Cyclization Followed by Oxidation. Issue 23 (20th May 2020)

• Record Type: Journal Article
• Authors: Kwak, Jung Pyo; Dao, Pham Duy Quang; Cho, Chan Sik
• Is Part Of: European journal of organic chemistry. Issue 23(2020)
• Page Start: 3468
• Page End: 3474
• Publication Date: 2020-05-20
• Subjects: Copper -- Cross‐coupling -- Cyclization -- Nitrogen heterocycles -- Oxidation; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.202000427
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract : 2‐(2‐Bromoaryl)‐ and 2‐(2‐bromovinyl)‐4, 7‐dimethoxybenzimidazoles are coupled and cyclized with cyanamide as a building block in dimethylformamide in the presence of a catalytic amount of a copper catalyst along with a base to give the corresponding 2‐aminoquinazoline‐ and 2‐aminopyrimidine‐fused 4, 7‐dimethoxybenzimidazoles in good yields. Subsequent oxidation of such N‐fused hybrid scaffolds by treatment of ceric ammonium nitrate in acetonitrile/H2 O affords unprecedented 2‐aminoquinazoline‐ and 2‐aminopyrimidine‐fused benzimidazolequinones. Abstract : An unprecedented synthesis of N‐fused hybrid scaffolds has been developed by initial copper‐catalyzed C–N coupling and cyclization of 2‐(2‐bromoaryl)‐ and 2‐(2‐bromovinyl)‐4, 7‐dimethoxybenzimidazoles with cyanamide as a building block followed by oxidation. Further challenges on the construction of amino‐group‐containing polynuclear N‐fused hybrid scaffolds using this method are expected.