Synthesis method of 5, 7-dichloro-1, 2, 3, 4-tetrahydroisoquinoline hydrochloride

The invention relates to a synthesis method of 5, 7-dichloro-1, 2, 3, 4-tetrahydroisoquinoline hydrochloride, and belongs to the technical field of synthesis of medical intermediates. The method comprises the steps that 3, 5-dichlorobenzaldehyde serves as a raw material, 5, 7-dichloro-1, 2, 3, 4-tetrahydroisoquinoline hydrochloride is obtained through Schiff base preparation, reduction, ring closing and reductive acidification reaction, and the total yield is 60% or above. The method avoids using expensive raw materials, and is simple in process route, mild in condition, low in production costand suitable for industrial production. 本发明涉及一种5,7-二氯-1,2,3,4-四氢异喹啉盐酸盐的合成方法，属于医药中间体合成技术领域。本发明所述的方法包括以3,5-二氯苯甲醛为原料，通过制备席夫碱、还原、关环及还原酸化反应得到5,7-二氯-1,2,3,4-四氢异喹啉盐酸盐，总收率在60％以上。本发明避免了使用昂贵的原料，且工艺路线简单，条件温和，生产成本低，适合工业化生产。