From Chemistry Towards Technology Step-By-Step From Chemistry Towards Technology Step-By-Step От химии к технологии шаг за шагом 2782-1900 96868 10.52957/2782-1900-2025-6-1-88-98 Научные статьи Scientific articles Научные статьи Intramolecular amination of ortho-nitro-tert-anilines as a method for the synthesis of condensed benzimidazole derivatives with a nodal nitrogen atom Intramolecular amination of ortho-nitro-tert-anilines as a method for the synthesis of condensed benzimidazole derivatives with a nodal nitrogen atom Бегунов Роман Сергеевич Begunov Roman Sergeevich begunov@bio.ac.ru

кандидат химических наук;

candidate of chemical sciences;

 Савина Луиза Ильинична Savina Luisa Ilyinichna luizasavina2000@mail.ru Астафьева Дария Александровна Astafieva Dariya Aleksandrovna cherry23_00@mail.ru Ярославский государственный медицинский университет Yaroslavl State Medical University Ярославский государственный университет им. П.Г. Демидова P.G. Demidov Yaroslavl State University 28 03 2025 28 03 2025 6 1 88 98 11 12 2024 06 02 2025 https://chemintech.ru/en/nauka/article/96868/view

The paper examines the applicability limits of the intramolecular reductive cyclisation reaction of ortho-nitroarenes containing various limiting azagetherocycles for the synthesis of condensed benzimidazole derivatives with a nodal nitrogen atom. The process of intramolecular heterocyclisation occurred during the reduction of 4-(2-nitroaryl)-4-morpholine and 1-(2-nitroaryl)-4-methylpiperidine. At the same time, the presence of the 4-methyl-piperazine cycle in the substrate prevented the formation of a condensed polyazaheterocycle.

The paper examines the applicability limits of the intramolecular reductive cyclisation reaction of ortho-nitroarenes containing various limiting azagetherocycles for the synthesis of condensed benzimidazole derivatives with a nodal nitrogen atom. The process of intramolecular heterocyclisation occurred during the reduction of 4-(2-nitroaryl)-4-morpholine and 1-(2-nitroaryl)-4-methylpiperidine. At the same time, the presence of the 4-methyl-piperazine cycle in the substrate prevented the formation of a condensed polyazaheterocycle.

 reductive intramolecular heterocyclisation ortho-nitro-tert-anilines condensed benzimidazole derivatives reductive intramolecular heterocyclisation ortho-nitro-tert-anilines condensed benzimidazole derivatives The work was performed under the State Assignment for research and development of Yaroslavl State Medical University for 2025 from the Ministry of Health of the Russian Federation on the topic ‘Development of new drugs for targeted chemotherapy of oncological diseases based on condensed benzimidazole derivatives with a nodal nitrogen atom’.

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