The invention provides a synthetic method for methyl caulophine. The method comprises the following steps: with
isovanillin and p-hydroxyanisole as raw materials, successively subjecting
isovanillin to bromination and
methylation so as to obtain 2-bromo-3,4- dimethoxy
benzaldehyde; successively subjecting p-hydroxyanisole to
acetylation, bromination, hydrolyzation, allyl etherification,
Claisen rearrangement and
methylation so as to obtain 1-allyl-4-bromo-2,5-dimethoxybenzene; successively subjecting the obtained 1-allyl-4-bromo-2,5-dimethoxybenzene and 2-bromo-3,4- dimethoxy
benzaldehyde to
Grignard reaction,
ruthenium chloride /
sodium periodate double-bond oxidation,
reductive amination,
pyridine chlorodichromate oxidation and intramolecular
coupling so as to obtain 3-(2-(N,N-dimethylamino)methyl)-1,4,5,6-tetramethoxyl-9-H-
fluorene-9-
ketone, i.e. the method for synthesizing methyl caulophine is completed. The method in the invention has the advantages of mild
reaction conditions, simple operation, easily-available raw materials and reagents, etc., and is suitable for large-scale production of pharmaceutical enterprises