The Direct Introduction of Carbonates α to Carbonyl Groups

Abstract

The first method for the direct formation of α-oxycarbonates from both aldehydes and ketones is described. N-Methyl-O-alkoxyformate hydroxylamine hydrochloride reagents can be prepared in two high-yielding steps from N-Boc-N-methyl hydroxyl­amine and were found to be bench stable. These were reacted with a variety of carbonyl compounds to give the corresponding α-functionalised products in 48-98% isolated yield via a proposed [3,3]-sigmatropic rearrangement.

Key words

metal-free synthesis - hydroxylamine - carbonate

References and Notes

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9

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