Internal alkynes have been shown to undergo oxidation to substituted benzils (1,2-diarylethane-1,2-diones) by α-picoline N-oxide in the presence of Ph 3 PAuNТf 2 (5 mol-%). In addition to the unsubstituted benzil, the method allows preparing, under markedly mild conditions (50 °C in chlorobenzene), various non-symmetrical products, including heteroaromatic versions thereof which are much more difficult to obtain otherwise. This gold(I)-catalyzed transformation was integrated into one-pot reaction sequence delivering a range of 5- to 7-membered ring systems (imidazoles, quinoxalines, 1,2,4-triazines, pyrazines, and 1,4-diazepines), thus linking these important heterocyclic motifs to the internal alkyne reagent space.
CITATION STYLE
Dubovtsev, A. Y., Dar’in, D. V., Krasavin, M., & Kukushkin, V. Y. (2019). Gold-Catalyzed Oxidation of Internal Alkynes into Benzils and its Application for One-Pot Synthesis of Five-, Six-, and Seven-Membered Azaheterocycles. European Journal of Organic Chemistry, 2019(8), 1856–1864. https://doi.org/10.1002/ejoc.201900108
Mendeley helps you to discover research relevant for your work.