Under the protection of nitrogen, 110 g (1 mol) of resorcinol and 220 g of n-heptane were mixed in the reaction flask, heated and dissolved, and the temperature was lowered to 10 ?? C. A turbid solution of 40.8 g (1.02 mol) of sodium hydroxide and 100 g of n-butanol was added in portions. , And control the temperature of 10 to 15 , after TLC (EA developing agent) detection of almost no remaining raw materials, add n-butanol (2.5mol), tris (pentafluorobenzene) borane 17.5g (0.1mol) and calcium chloride 1.1 g, raise the temperature to 40-45 ?? C for 1 hour, then raise the temperature to 98 ?? C for reflux and water separation. After 8 hours of water separation, take a sample and quench the GC to detect resorcinol <1%, cool to room temperature, add a small amount of water to quench It is extinguished, and then dilute sulfuric acid is added to adjust the pH = 1-2. The insoluble solids are filtered through diatomaceous earth, and the organic phase is concentrated to a stagnant liquid. Water is added for replacement, and then 660 g of water, 2.2 g of sodium thiosulfate, and 5.5 g are added. Activated carbon was heated to reflux for 1 hour, and was hot-filtered to obtain a pale yellow solution. Then, flaky crystals were precipitated by cooling, and 151 g of 4-n-butylresorcinol was obtained by filtration, GC: 99.3%, and yield: 90.9%.