Cyclobutanone → HCID 69055903, compound

Participants

Reaction Steps

To a solution of 3-acetyl-2-ethyl-4-hydroxy-5,6-dimethylphenyl acetate (3.5 g) in 20 mL of toluene was added cyclobutanone (1.16 mL) and pyrrolidine (1.4 mL). The reaction was allowed to reflux for 2 hours and Dean-Stark apparatus was used to remove water from the reaction. After the reaction was complete, the mixture was extracted with ethyl acetate and then was washed with 1N HCl and water. The organic layer was dried over anhydrous Na2SO4 and concentrated in vacuo to give 5-ethyl-7,8-dimethyl-4-oxo-3,4-dihydrospiro[chromene-2,1′-cyclobutan]-6-yl acetate, which was hydrolyzed in 1N NaOH in MeOH/water. After the reaction was complete as indicated by TLC, the mixture was acidified with 1N HCl and extracted with ethyl acetate and dried over anhydrous Na2SO4. Evaporation of the solvents gave 0.8 g of 5-ethyl-6-hydroxy-7,8-dimethylspiro[chromene-2,1′-cyclobutan]-4(3H)-one as a yellow paste.

Provenance & Evidence