本发明涉及一种苯并咪唑-2-甲醛的合成工艺,包括如下步骤:以羟基磷灰石粉末为催化剂,以46℃~58℃热水作为溶剂,以邻苯二胺和乙醛酸为原料进行反应,所述邻苯二胺和乙醛酸的摩尔比为1:(1~1.2),反应时间为(2-10)小时,反应温度为46℃~58℃,反应结束后,趁热过滤,将滤液冷却至0℃~ The invention relates to a synthesis process of benzimidazole-2-formaldehyde, which comprises the following steps: taking hydroxyapatite powder as a catalyst, hot water of 46 DEG C-58 DEG C as a solvent, o-phenylenediamine and glyoxylic acid as The molar ratio of o-phenylenediamine to glyoxylic acid is 1: (1~1.2), the reaction time is (2-10) hours, the reaction temperature is 46~58 ° C. After the reaction is over, Heat filtration, the filtrate was cooled to 0 ℃ ~