Water → HCID 69054367, compound

Participants

Reaction Steps

To a solution 3-acetyl-4-hydroxy-2,6-dimethylphenyl acetate (13 g) and cyclobutanone (4.5 g) in toluene (150 mL) was added pyrrolidine (5.4 mL, 4.6 g). The solution was stirred at room temperature for 15 min and then refluxed for 5 hours equipped with Dean-Stark water trap. The solution was diluted with ethyl acetate, washed with diluted hydrochloride acid water solution, water and brine. Evaporation and chromatography (silica gel, hexane-ethyl acetate 1% to 10%) gave 5.5 g of 5,7-dimethyl-4-oxo-3,4-dihydrospiro[chromene-2,1′-cyclobutan]-6-yl acetate and 3.2 g of 6-hydroxy-5,7-dimethylspiro[chromene-2,1′-cyclobutan]-4(3H)-one.

Provenance & Evidence