Abstract: First intermediate,4,5-dimethoxysalicylaldehyde was synthesized by demethylation of 2,4,5-trimethoxybenzaldehyde with boron tribromide.The yield is about 64%.Then second intermediate 4,5-dimethoxy-2-hydroxy ethyl phenylacrylate was prepared from the first intermediate by reaction with ethyl malonate and the yield is about 79%.Finally the targeted product 6,7-dimethoxycoumarin was synthesized from the second intermediate via cyclization with thionyl chloride and yield is about 51%.All the intermediates and product were characterized by ¹HNMR and MS.The results showed that the targeted intermediates and product were prepared as required.

Key words: fragrance, 6,7-dimethoxycoumarin, demethylation, condensation, cyclization