5,6-Dimethoxynaphthalene-2-carboxylic acid was synthesized in 7 steps and with an overall yield of 46%. Bromination of 2-naphthol, and methylation with dimethyl sulfate followed by Friedel-Crafts acylation with AcCl gave 2-acetyl-5-bromo-6-methoxynaphthalene. 2-Acetyl-5-bromo-6-methoxynaphthalene was converted to 5-bromo-6- methoxynaphthalene-2-carboxylic acid by a haloform reaction. The esterification of the acid with methanol, methoxylation with NaOCH_3 in the presence of CuI and subsequent de-esterification with NaOH afforded 5,6-dimethoxynaphthalene-2-carboxylic acid. The 5-bromo-6-methoxynaphthalene-2-carboxylic acid and 5,6-dimethoxynaphthalene-2-carboxylic acid were found to have in vitro antibacterial activity against some pathogenic bacteria.
Naphthalene-2-carboxylic acids, 2-naphthol, bromination, haloform, antibacterial activity
GÖKSU, SÜLEYMAN; UĞUZ, METİN TANSU; ÖZDEMİR, HASAN; and SEÇEN, HASAN (2005) "A Concise Synthesis and the Antibacterial Activity of 5,6-Dimethoxynaphthalene-2-carboxylic Acid," Turkish Journal of Chemistry: Vol. 29: No. 2, Article 12. Available at: https://journals.tubitak.gov.tr/chem/vol29/iss2/12