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DOI: 10.1055/sos-SD-213-00070

Ballini, R.; Petrini, M.Science of Synthesis: C-1 Building Blocks in Organic Synthesis, (20142142.

Formation of nitromethyl radicals by oxidation with metallic compounds, although possible, has been barely used for synthetic purposes. The nitromethyl radical addition to aryl derivatives and simple alkenes is known, but the yield of the corresponding adducts hardly exceeds 50%. Furthermore, a large excess of the oxidant is often required (up to 4 equiv) curtailing the sustainability of the process. The nitromethyl radical is generated by a single-electron-transfer oxidation of the corresponding methanenitronate anion by ammonium cerium(IV) nitrate in the presence of electron-rich alkenes such as glycal 28 (Scheme 12).[‌26‌] The corresponding anti-adducts 29 and 30 are obtained as a diastereomeric mixture with a prevalence of the α-anomer 29. This process is oriented at the synthesis of glycosamines, which can be obtained by reduction of the nitro group under various conditions, including treatment with lithium aluminum hydride or catalytic hydrogenation in the presence of palladium on charcoal. The latter procedure also allows the concurrent cleavage of the benzyloxy groups.

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