To a stirring solution of 5-(4-ethoxy-2-hydroxy-3-methoxyphenyl)isobenzofuran-1(3H)-one (80 mg, 0.266 mmol) in acetonitrile (7 mL) was added potassium carbonate (110 mg, 0.798 mmol) and 3-bromo-2,2-dimethylpropan-1-ol (134 mg, 0.798 mmol) and the resultant reaction mixture was heated to 80° C. for 16 h. The reaction mixture was cooled to RT, filtered through celite and the filtrate was concentrated under reduced pressure. Purification of the residue by flash column chromatography (silica gel, 0-25% ethyl acetate in pet ether) afforded title compound as a solid (15 mg, 14.7%).
