Cycloaddition Reactions of In Situ Generated C2D2 in Dioxane: Efficient Synthetic Approach to D2-Labeled Nitrogen Heterocycles

In this work, a universal synthetic approach to the synthesis of D2-labeled nitrogen heterocycles based on cycloaddition reactions of in situ generated dideuteroacetylene is reported. A key feature of the developed method is the use of dioxane as a deuterium-exchange-proof solvent, which allowed dideuterosubstituted heterocycles to be obtained in up to 99% deuteration. The developed method was demonstrated to be suitable for the synthesis of D2-labeled triazoles, isoxazoles, pyrazoles and pyridazines.

Reference: Eur. J. Org. Chem., 2021, ASAP

DOI: 10.1002/ejoc.202101085