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Dearomative (3 + 2) and (4 + 2) Cycloadditions of [1,2,4]Triazolo[1,5-a]pyridines: Rapid Access to Polycyclic

Andrey Kruchinin1, Maxim Bastrakov1, Mikhail Minyaev1

  • 1N. D. Zelinsky Institute of Organic Chemistry, Leninsky prospect, 47, 119991 Moscow, Russian Federation.

The Journal of Organic Chemistry
|November 10, 2025
PubMed

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Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
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