Marriage of Peroxides and Nitrogen Heterocycles: Selective Three-Component Assembly, Peroxide-Preserving Rearrangement, and Stereoelectronic Source of Unusual Stability of Bridged Azaozonides

• DOI: 10.1021/jacs.1c02249
• Publication Date: 2021-04-21T23:53:14Z
• Authors: Ivan A. Yaremenko; Yulia Yu. Belyakova; Peter S. Radulov; Roman A. Novikov; Michael G. Medvedev; Nikolai V. Krivos...; Alexander A. Korl...; Igor V. Alabugin; Alexander O. Tere...
• Keywords: Peroxide; Moiety; Amide

Stable bridged azaozonides can be selectively assembled via a catalyst-free three-component condensation of 1,5-diketones, hydrogen peroxide, and an NH-group source such as aqueous ammonia or ammonium salts. This procedure is scalable produce gram quantities bicyclic stereochemically rich heterocycles. The new are thermally stable stored at room temperature for several months without decomposition least 1 year −10 °C. chemical stability was explored their subsequent selective transformations including the first example aminoperoxide rearrangement that preserves peroxide group. amino group in aminoperoxides has remarkably low nucleophilicity does not participate usual amine alkylation acylation reactions. These observations 15 pKa units decrease basicity comparison with typical dialkyl attributed to strong hyperconjugative nN→σ*C–O interaction two antiperiplanar C–O bonds. Due weakness complementary nO→σ*C–N donation from oxygens (a consequence "inverse α-effect"), this depletes electron density NH moiety, protects it oxidation, makes similar properties amide.