Electrooxidation Based Strategy Towards the Core 3-Amino-6-Hydroxy­azepan-2-one

Abstract

We describe a practical synthesis of protected (3S,6R)-6-hydroxy-cyclolysine derivatives starting from cyclic l-lysine. ­Evaluation of the electrochemical oxidation of various protected amino-caprolactams allowed a regioselective electromethoxylation at the α-position to the lactam nitrogen. Formation of the corresponding enamide by elimination of methanol followed by a diastereoselective dihydroxylation, diacetylation and subsequent regioselective reduction afford the orthogonally protected (3S,6R)-3-amino-6-hydroxy-azepan-2-one.

bengamides - diastereoselectivity - dihydroxylation - electrooxidation - osmium

References

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