Bromination of 2,7-Dihydroxynaphthalene

Abstract

Bromination of 2,7-dihydroxynaphthalene gives a mixture of two dibromo derivatives which are now identified as the 1,6- and 1,3-isomers. Reduction of these compounds gives the new 3-bromo-2,7-dihydroxpphthalene. Similar reduction of 1,3,6-tribromo-2,7-dihydroxynaphthalene gives the previously unknown 3,6-dibromo-2,7-dihydroxynaphthalene. After methylation this is readily converted into 2,7-dimethoxynaphthalene-3,6-dicarboxylic acid by carbonation of the lithium derivative. It has not been possible to substantiate claims that 2,7-dihydroxynaphthalene and its dimethyl ether give 1,3,6,8-tetrabromo derivatives.