The synthesis of 4-N-BUTOXYBENZYL BROMIDE is as follows:Under the protection of nitrogen,Add 40g of compound 5-1 to a 1L reaction flask,50g hydrogen bromide solution (hydrogen bromide concentration is 40wt%) and 500mL toluene,After fully dissolving, control the temperature between 110130,The reaction was stirred for 5h.Add 300 mL of ethyl acetate and 400 mL of water to the reaction solution for extraction,Collect the ethyl acetate layer, add anhydrous sodium sulfate for drying, then concentrate,Obtain 40 g of white solid (compound 6-1),The yield was 74.12%.