Bromination of tetralin. Short and efficient synthesis of 1,4-dibromonaphthalene

High-temperature bromination of tetralin (1,2,3,4-tetrahydronaphthalene) wi th bromine resulted in benzylic bromination to give 1,4-dibromo-1,2,3,4-tet rahydronaphthalene (4) as a major product and several secondary products. P hotolytic bromination of tetralin and subsequent double dehydrobromination of 1,1,4,4-tetrabromo-1,2,3,4-tetrahydronaphthalene (10) gave 1,4-dibromona phthalene (11) as the sole product in a high yield. 1,4-Dibromonaphthalene is efficiently converted to the corresponding methoxy (12 and 13) and cyano (14 and 15) derivatives of naphthalene.