BrBr.COC1C=CC2C(=CC=CC=2)C=1.Br.Br[C:17]1[C:26]2[C:21](=[CH:22][C:23]([Br:27])=[CH:24][CH:25]=2)[CH:20]=[CH:19][C:18]=1[O:28][CH3:29]>CC(O)=O.O.[Fe]>[CH3:29][O:28][C:18]1[CH:19]=[CH:20][C:21]2[C:26](=[CH:25][CH:24]=[C:23]([Br:27])[CH:22]=2)[CH:17]=1
A solution of 81 g of bromine in 25 cm3 of CH3COOH was added over 35 minutes to a very well stirred suspension of 39.25 g of 2-methoxy-naphthalene in 125 cm3 of glacial CH3COOH, heated to 30° C., keeping the temperature at 40°-45° C., avoiding that the formed hydrobromic acid leaves the reaction medium; when the addition was over, the bulk was stirred for 1.5 h at 45° C. in order to complete the reaction. 14 g of iron in the form of powder were then added, in small doses, over 1.5 hours, slowing down at intervals the reaction exothermicity by means of a cold bath; one stirred at 45° C. till 1,6-dibromo-2-methoxy-naphthalene disappeared (on thin layer chromatography) and then the bulk was diluted with 0.5 liters of H2O. Then the compound was filtered, washed with H2O and dissolved in CH2Cl2 ; lastly the chloromethylenic solution was washed with NaOH at 5%, dehydrated and evaporated. 55.2 g of raw 2-methoxy-6-bromo-naphthalene were obtained; after a crystallization from 250 cm3 of isobutanol, 45 g of pure product were obtained (gas-chromatographic analysis) having a melting point ranging between 105° and 106° C.
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