TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): Preparation of (I), comprises carrying out Heck reaction of benzophenone compounds of formula (II). Preferred method: The method comprises adding (II), palladium acetate, triphenylphosphine and sodium acetate into a reaction container, vacuuming, then adding anhydrous N,N-dimethylacetamide, again vacuuming, and reacting at 100-150 degrees C for 12-24 hours in an oil bath under nitrogen protection, then cooling the reaction mixture to room temperature, filtering, adding water, extracting with ethyl acetate, collecting organic phase and drying, and removing the solvent by vacuum distillation to obtain (I), where molar ratio between (II), palladium acetate, triphenylphosphine and sodium acetate is 1:0.2-0.3:0.4-0.5:1-2.5, and then purifying (I) by performing silica gel column chromatography using petroleum ether and ethyl acetate in a volume ratio of 2:1 as eluent. The method further comprises adding potassium acetate, anhydrous potassium carbonate, tetrakis(triphenylphosphine)palladium, 2-dicyclohexylphosphino-2'-(N,N-dimethylamino)biphenyl and anhydrous N,N-dimethylacetamide into a reaction vessel under vacuum, pre-reacting at room temperature for 10-20 minutes, then adding N,N-dimethylacetamide solution of (II) into the reaction mixture, passing protective gas, vacuuming, and reacting at 100-150 degrees C for 12-24 hours in an oil bath under protective atmosphere, then cooling, filtering, adding water, extracting with ethyl acetate, collecting organic phase and drying, and then removing the solvent by vacuum distillation to obtain (I), where molar ratio of (II), potassium acetate, potassium carbonate, triphenylphosphine and 2-dicyclohexylphosphino-2'-(N,N-dimethylamino)biphenyl is 1:1.5-2:1.5-2:0.02-0.06:0.05-0.1. The silica gel column is packed with 300-400 mesh silica gel, and the eluent is mixture of petroleum ether and ethyl acetate in a volume ratio of 7:1. Preparation of (II), comprises reacting benzene compounds of formula (III) with magnesium in an organic solvent to obtain a Grignard reagent, then carrying out addition reaction with benzaldehyde compounds of formula (IV), and hydrolyzing to obtain benzhydrol compounds, and then performing oxidation reaction of benzhydrol compounds to obtain (II). Preparation of (II) further comprises: (a) either mixing ammonium chloride solution and activated anhydrous magnesium turnings in a reaction vessel, vacuuming, then adding iodine tablets, adding a portion of (III) dissolved in an organic solvent, heating while stirring to initiate the reaction, then adding the remaining portion of (III) dissolved in an organic solvent, and refluxing at room temperature, then cooling in an ice-bath, adding (IV), and reacting at room temperature, adding saturated ammonium chloride solution, hydrolyzing, distilling off the organic solvent, extracting with ethyl acetate, collecting organic phase, washing with water and saturated sodium chloride solution, and evaporating the solvent to obtain benzhydrol compounds; or adding ammonium chloride solution and activated anhydrous magnesium bar into a reaction vessel, then adding iodine tablets, vacuuming and heating to volatilize magnesium adhered to surface of the vessel, adding (III) dissolved in an organic solvent, heating and refluxing, then cooling to room temperature in an ice-water bath, adding (IV) and reacting, adding saturated ammonium chloride solution, hydrolyzing, distilling off the organic solvent, extracting with ethyl acetate, collecting organic phase, washing with water and saturated sodium chloride solution, and evaporating the solvent to obtain benzhydrol compounds, where (III) and (IV) are dissolved in anhydrous tetrahydrofuran, and molar ratio between (III), magnesium and (IV) is 1:1.5:1; and (b) dissolving benzhydrol compounds in an organic solvent, adding oxidizing agent pyridinium chlorochromate, and carrying out oxidation at room temperature for overnight, then filtering through diatomaceous earth, and concentrating under reduced pressure to obtain (II), where molar ratio between pyridinium chlorochromate and benzhydrol compounds is 1-3:1.R3 = not defined.