-_ addition to a slurry of AlC13 in 1, 2-dichloroethane at room temperature. At least 4 equiv of A1Cl3 were necessary for optimum results; in practice, we utilized 4.6 equiv of A1C13 Workup shortly thereafter afforded the N-acetyldihydroisoquinolines 3. The yields of monohalo products 3a-d ranged from 35 to 55%, while the dichloro products 3e, f were obtained consistently in 6040% yield. The mildness of the cyclization conditions is ...