Aluminum Amalgam for the Reduction of Sensitive β-Nitroamines to 1,2-Diamines

Abstract

A two-step reduction protocol for the conversion of a range of sensitive β-nitroamines to 1,2-diamines has been developed that is operationally simpler, cheaper and higher-yielding than the previously reported SmI₂ protocol. Reduction of the nitro function to a hydroxylamine was achieved with Al amalgam and then reduced to the 1,2-diamine product with H₂, Pd/C or LiAlH₄ with no erosion of diastereoselectivity. A representative selection of 9 β-nitroamines were reduced in 71-94% yield.

Key words

reduction - aluminum - amines - β-nitroamine - 1,2-diamine

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