Effective microwave-assisted approach to 1,2,3-triazolobenzodiazepinones via tandem Ugi reaction/catalyst-free intramolecular azide–alkyne cycloaddition

Authors

Maryna O. Mazur, State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of Ukraine, V. N. Karazin Kharkiv National University
Oleksii S. Zhelavskyi, State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of Ukraine, University of Michigan – Ann Arbor
Eugene M. Zviagin, State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of Ukraine, University of Nebraska – Lincoln
Svitlana V. Shishkina, State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of Ukraine
Vladimir I. Musatov, State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of Ukraine
Maksim A. Kolosov, V. N. Karazin Kharkiv National University
Elena H. Shvets, V. N. Karazin Kharkiv National University
Anna Yu. Andryushchenko, State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of Ukraine
Valentyn A. Chebanov, State Scientific Institution “Institute for Single Crystals” of National Academy of Sciences of Ukraine, V. N. Karazin Kharkiv National University

Date of this Version

3-8-2021

Citation

Beilstein J. Org. Chem. 2021, 17, 678–687. https://doi.org/10.3762/bjoc.17.57

Comments

Open Access

Abstract

A novel catalyst-free synthetic approach to 1,2,3-triazolobenzodiazepinones has been developed and optimized. The Ugi reaction of 2-azidobenzaldehyde, various amines, isocyanides, and acids followed by microwave-assisted intramolecular azide–alkyne cycloaddition (IAAC) gave a series of target heterocyclic compounds in moderate to excellent yields. Surprisingly, the normally required ruthenium-based catalysts were found to not affect the IAAC, only making isolation of the target compounds harder while the microwave-assisted catalyst-free conditions were effective for both terminal and non-terminal alkynes