Expanding Stereoelectronic Limits of endo- tet Cyclizations: Synthesis of Benz[ b]azepines from Donor-Acceptor Cyclopropanes

The importance of intramolecular constraints in cyclic transition-state geometries is especially pronounced in n-endo-tet cyclizations, where the usual backside approach of a nucleophile to the breaking bond is impossible for the rings containing less than eight atoms. Herein, we expand the limits of endo-tet cyclizations and show that donor-acceptor cyclopropanes can provide a seven-membered ring via a genuine 6-endo-tet process. Substrates containing a N-alkyl-N-arylcarbamoyl moiety as an acceptor group undergo Lewis acid-induced cyclization to form tetrahydrobenz[b]azepin-2-ones in high yields. The reaction proceeds with the inversion of the configuration at the electrophilic carbon. In this process, a formally six-membered transition state yields a seven-membered ring as the pre-existing cycle is merged into the forming ring. The stereochemistry of the products can be controlled by the reaction time and by the nature of Lewis acid, opening access to both diastereomers by tuning of the reaction conditions. © 2021 American Chemical Society.

Авторы
Vartanova A.E. 1, 2 , Plodukhin A.Y.3 , Ratmanova N.K.4 , Andreev I.A.1, 4 , Anisimov M.N.5, 6 , Gudimchuk N.B.5, 6 , Rybakov V.B. 3 , Levina I.I.7 , Ivanova O.A. 1, 3 , Trushkov I.V. 1 , Alabugin I.V.8
Издательство
American Chemical Society
Номер выпуска
34
Язык
Английский
Страницы
13952-13961
Статус
Опубликовано
Том
143
Год
2021
Организации
  • 1 N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, 119334, Russian Federation
  • 2 Faculty of Science, RUDN University, Moscow, 117198, Russian Federation
  • 3 Department of Chemistry, M. V. Lomonosov Moscow State University, Moscow, 119991, Russian Federation
  • 4 Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, 117997, Russian Federation
  • 5 Department of Physics, M. V. Lomonosov Moscow State University, Moscow, 119991, Russian Federation
  • 6 Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, 119334, Russian Federation
  • 7 Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, 119334, Russian Federation
  • 8 Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306-4390, United States
Ключевые слова
Propane; Acceptor groups; Cyclic transitions; Diastereomers; Donor-acceptor cyclopropanes; Electrophilic carbon; Reaction conditions; Seven-membered rings; Transition state; Cyclization
Дата создания
16.12.2021
Дата изменения
16.12.2021
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/76677/
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