Synthesis of Unsymmetrical β-Enamino Ketones

Abstract

A convenient procedure for modification of β-enaminones by α-C-acylation and subsequent acidic cleavage is described. The unsymmetrical β-enamino ketones obtained in this way could be hydrolyzed to provide an entry towards various unsymmetrical 1,3-diketones.

Key words

enaminones - C-acylation - cleavage - 1,3-diketones - unsymmetrical

References

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1

Dr Atanas Venkov passed away suddenly on July 21st, 2003, aged 62.

7

The phosphoric acid used in these experiments was obtained by adding P₂O₅ (39.4 g) to 85% H₃PO₄ (d = 1.7, 58.82 mL/100 g).