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Synthesis of N-Fused Benzimidazole-4,7-diones via Sequential Copper-Catalyzed C-N Coupling/Cyclization and Oxidation.

ABSTRACT: 2-(2-Bromovinyl)- and 2-(2-bromoaryl)-benzimidazoles, including their 4,7-dimethoxy analogs, react with primary amides by microwave irradiation (or usual heating) in dimethylformamide in the presence of a catalytic amount of CuI along with a base to give the corresponding benzo[4,5]imidazo[1,2-c]-pyrimidines and -quinazolines in good yields. Treatment of benzo[4,5]imidazo[1,2-c]-pyrimidines and -quinazolines having methoxy group on benzimidazole moiety with aqueous ceric ammonium nitrate affords unprecedented N-fused hybrid scaffolds, benzo[4,5]imidazo[1,2-c]-pyrimidin-6,9-diones and -quinazoline-8,11-diones, respectively, in high yields.

SUBMITTER: Dao PDQ

PROVIDER: S-EPMC6642034 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Synthesis of N-Fused Benzimidazole-4,7-diones via Sequential Copper-Catalyzed C-N Coupling/Cyclization and Oxidation.

Dao Pham Duy Quang PDQ Ho Son Long SL Cho Chan Sik CS

ACS omega 20180525 5

2-(2-Bromovinyl)- and 2-(2-bromoaryl)-benzimidazoles, including their 4,7-dimethoxy analogs, react with primary amides by microwave irradiation (or usual heating) in dimethylformamide in the presence of a catalytic amount of CuI along with a base to give the corresponding benzo[4,5]imidazo[1,2-<i>c</i>]-pyrimidines and -quinazolines in good yields. Treatment of benzo[4,5]imidazo[1,2-<i>c</i>]-pyrimidines and -quinazolines having methoxy group on benzimidazole moiety with aqueous ceric ammonium n ...[more]

PMID: 31458764

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