一种苯乙醛的合成方法,1,3-二苄基苯并咪唑盐在惰性气体保护下,加入到苄基氯化镁溶液中,搅拌反应混合物12~24h,将饱和草酸溶液滴加到反应混合物中,60~80℃温水浴中搅拌1~3h,蒸去溶剂,用乙醚萃取,蒸馏得纯品;本发明的苯乙醛的合成方法,以苯并咪唑盐为原料,原料分子中没有可与镁盐形成络合物的氧原子,避免了副产物氨基醇 A method for the synthesis of phenylacetaldehyde, 1,3-dibenzyl benzimidazolium salt under inert gas protection, was added to the benzyl magnesium chloride solution, the reaction mixture was stirred for 12 ~ 24h, a saturated solution of oxalic acid was added dropwise to the reaction mixture , Stirring at 60 ~ 80 ℃ warm water bath for 1 ~ 3h, evaporating the solvent, extracting with ether and then distilling to obtain pure product; the method for synthesizing phenylacetaldehyde of the present invention uses benzimidazolium salt as raw material, Oxygen atoms that form complexes with magnesium salts, avoid by-product aminoalcohols