合成路线1

Friedel-Crafts acylation of 2-methylbenzofuran (I) with p-anisoyl chloride (II) in the presence of SnCl4 afforded the benzoyl benzofuran derivative (III). Ketone (III) reduction to the corresponding benzyl benzofuran (IV) was accomplished employing either LiAlH4 or NaBH4 and ZnI2. The methyl ether group of (IV) was then cleaved with melted pyridine hydrochloride to give phenol (V). Aromatic iodination of (V) with either I2/KI or with ICl in morpholine led to the diiodo phenol (VI). This was then alkylated with ethyl bromoacetate (VII) to furnish ester (VIII), which was finally hydrolyzed with NaOH to the target carboxylic acid.