Synthesis of Novel Substituted Phenols by Condensation of α,β-Unsaturated β-Dimethylaminoaldehyde Aminals with Triketones

Condensation of α,β-unsaturated β-dimethylaminoaldehydes with heptane-2,4,6-trione unexpectedly affords a new type of substituted phenols (4a–c; 5a,c) due to intramolecular cyclization accompanied by 1,6-deamination.