Sulfuric Acid → HCID 53641044, compound

Participants

Reaction Steps

800 g. of crude 3,5,5-trimethyl-2-cyclohexen-1-on-4-carboxylic acid methyl ester prepared in Example 1, and 720 g. of triethyl orthoformate were mixed with 1.5 l. of anhydrous ethanol containing 4 ml. of sulfuric acid. After standing for 4 hours at room temperature, the dark blue solution was poured onto petroleum ether over a sodium bicarbonate solution. The ether layer was washed twice with water, dried over sodium sulfate, and concentrated by removing all of the ether solvent. The resulting dark residue was distilled over a vigreux column under high vacuum to yield 2,6,6-trimethyl-4-ethoxy-1,3-cyclohexadien-1-carboxylic acid methyl ester.

Provenance & Evidence