Functionalization of Internal Arylalkynes with Nitrosylsulfuric Acid: Access to Arylated 1,2-Diketones and
Oksana B Bondarenko1, Anastasiya V Staroverova1, Georgy L Karetnikov1
1Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow, Russian Federation.
Abstract:
Nitrosylsulfuric acid was found to be an efficient oxidant for converting internal arylalkynes into their corresponding benzils. This 1,2-dicarbonylation proceeds under mild conditions at ambient temperature in nitromethane in the presence of catalytic amounts of iodine, affording benzils in 30-99% yields. Replacing nitromethane with acetonitrile crucially influences the composition of the products, with the main reaction products being substituted 1,3-oxazoles. The mechanism of the transformations was investigated by experiments with H218O.
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