To a solution of 3-benzo[1,3]dioxol-5-yl-5-(4-methoxy-benzyloxy)-benzonitrile (500 mg) in anhydrous THF (10 mL) were added a solution of isopropylmagnesium chloride (2.1 mL of 2 M solution in diethyl ether) and catalytic amount of cuprous bromide (4 mg). The resulting reaction mixture was refluxed for 2 h. After it was cooled down, 10% sulfuric acid (5 mL) was added and stirring was continued for 30 min at room temperature. Then the reaction mixture was diluted with diethyl ether, washed with water and brine. The organic extract was dried over anhydrous sodium sulfate, concentrated and purified on a silica gel column using ethyl acetate and hexanes to yield 358 mg of the title compound (64% yield). HRMS calcd for C25H24O5 [M+H]+ 405.1697, observed 405.1698.
