35202-54-1

4,5-Dimethoxy-1-cyanobenzocyclobutane is used in the preparation of selective bradycardic agents.

NaNH2 (39.0 g, 1.0 mol) was added in portions to a solution of hydrocinnamonitrile 8 (224.0 g, 0.83 mol) in liquid ammonia at -45°C, and the reaction mixture was stirred at -45 °C for 2 h. After evaporation of the excess NH3, NH4Cl (20.0 g) and water (1000 mL) were added in portions. After standing at room temperature, greyish crystals separated and were collected and recrystallised with ethanol to give 4,5-Dimethoxy-1-cyanobenzocyclobutane as a colourless powder. Yield 116.5 g (74%).

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