Abstract
The aldol condensation products, 5-alkyl-4, 6-diacetyl-3-hydroxy-3-methylcyclohexanone (R=H, CH3, C6H5) and 3, 5-diacetyl-2, 6-heptanedione formed from 2, 4-pentanedione and aldehydes underwent further reactions involving aldol condensations and dehydrations on heating with the liquid formate, TEAF, given by 5HCO2H·2NEt3. These reactions finally gave the two isomers of dimethylbicyclo [3.3.1] nonadienediones. In the case of the formaldehyde condensation products, formate reactions giving 4, 6-diacetyl-3-methylcyclohex-2-en-1-one and 2, 4-diacetyl-5-methylphenol were also realized.