Aluminum isopropoxide → Zeranol

온도

75 °C

Aluminum isopropoxide (300 g, 1.4688 moles) is added to a solution of Zearalenone (100 g, 0.3141 moles) in 1000 g (1270 mL) of 2-propanol. The mixture is stirred at 75° C. for 24 hours then the mixture is distilled to a volume of about 500 mL, cooled to ambient room temperature, 400 mL of water and 550 mL of 6N HCl are added ensuring that the reaction temperature is maintained below 40° C. The reaction is cooled to ambient room temperature and 886 g (990 mL) of ethyl acetate is added. The aqueous layer is separated and the ethyl acetate layer is extracted 2×325 mL with water and 1×325 mL with brine. The ethyl acetate is replaced with methanol by distilling off the ethyl acetate and replacing it with 380 g (480 mL) of methanol. The methanol mixture is filtered to remove insoluble matter and 10% Palladium on carbon (10 g) is added followed by hydrogen (1 atmosphere of pressure) at ambient room temperature. The reaction is stirred for 8 hours then Celite (20 g) is added and the reaction stirred for an additional hour. The reaction mixture is filtered to remove insoluble matter and water (725 mL) is added. The mixture is stirred at ambient room temperature for 4 hours during which time solid precipitate. The solids are isolated by filtration and washed with heptane (1000 mL). The solids are dissolved in methanol (890 mL) and water (470 mL) is added at ambient room temperature and solids begin to crystallize from solution. The mixture is stirred for an additional 4 hours and the solids are isolated by filtration, dried under vacuum to a moisture content of less than 0.5% to yield pure Zeranol (45.6 g, 45%).