A Convenient Synthetic Access to δ-Amino-γ,γ-difluoro-β-ketoesters

Abstract

The zinc-cuprous chloride promoted Reformatsky-imine addition reaction of 4-bromo-4,4-difluoroacetoacetate with ald­imines derived from aromatic aldehydes and with ketimines derived from aryl alkyl ketone provided an efficient and practical access to δ-amino-γ,γ-difluoro-β-ketoesters. The scope and limitation of this procedure are also discussed.

Key words

difluorinated amines - imines - zinc - cuprous chloride - 4-bromo-4,4-difluoroacetoacetate

References

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13

Some of the signals in aryl and alkene region are not assigned in ¹³C NMR spectra due to complexity, since the spectrum is obtained from a mixture of keto ester enol ester and hydrate form.