The Direct Formation of α-Carbamates from Carbonyl Compounds

Abstract

A simple one-pot method for the direct introduction of carbamates α to carbonyl groups that proceeds at room temperature in the presence of both moisture and air has been developed. Treatment of aldehydes and both cyclic and acyclic ketones with N-­methyl-O-carbamoyl hydroxylamine hydrochlorides provides the α-functionalised products in 50-88% isolated yield. The trans­formation is tolerant of a range of functional groups within the ­substrate and is also effective for the introduction of a variety of ­oxycarbamoyl groups.

Key words

metal-free synthesis - hydroxylamine - carbamate - array methods

References and Notes

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8

All compounds prepared were characterised by mp, IR, ¹H NMR, ¹³C NMR, MS and HRMS.