Nitromethane → (E)-2-(Benzyloxy)-1-(2-ethoxyethoxy)-4-(2-nitrovinyl)benzene

Ammonium acetate (4.16 g, 53.9 mmol) and nitromethane (6.1 mL, 113 mmol) were added to a solution of 3-(benzyloxy)-4-(2-ethoxyethoxy)benzaldehyde described in Production Example 24-2 (13.5 g, 45.0 mmol) in acetic acid (36 mL) under nitrogen atmosphere at room temperature. The liquid mixture was heated and stirred under reflux at 130° C. for 2 hours. The reaction liquid was allowed to stand to cool to room temperature. The precipitate was collected by filteration and washed with ethanol to quantitatively obtain the title compound.