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Synthesis of Primary Amines via Hydrogen Atom Transfer-Initiated Cyclization/Reduction Cascade of Unsaturated
Henry Lindner1, Michael Schneider1, Philipp Mader1
1Laboratory of Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zurich, Switzerland.
Abstract:
We report a hydrogen atom transfer-initiated cyclization/reduction cascade for the synthesis of primary amines from δ,ε- and ε,ζ-unsaturated nitriles. The HAT transformation employs Mn(acac)3 as a catalyst and utilizes air as an oxidant along with NaBH4 as a dual-purpose reductant toward the olefin and subsequently C═N. Aromatic and aliphatic nitriles incorporating mono-, di-, and trisubstituted olefins are substrates for the reaction. Starting materials bearing malonates are transformed into the corresponding bicyclic lactams, enabling the rapid buildup of structural complexity.
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