[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH3:13])=[C:6]2[C:10]=1[C:9](=[O:11])[CH:8]([CH3:12])[CH2:7]2.[BH4-].[Na+].Cl.[OH-].[K+].[CH3:19]I>C1COCC1.O.CO>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH3:13])=[C:6]2[C:10]=1[CH:9]([O:11][CH3:19])[CH:8]([CH3:12])[CH2:7]2To a mixture of 74.0 g (0.310 mol) of 7-bromo-2,4-dimethylindan-1-one and 5.86 g (0.155 mol) of NaBH4 in 310 ml of THF 155 ml of methanol was added dropwise by vigorous stirring for 5 h at 0-5° C. This mixture was stirred overnight at room temperature and then added to 1 liter of cold water. The resulting mixture was acidified by 2 M HCl to pH˜5, and then it was extracted with 3×250 ml of dichloromethane. The combined organic extract was dried over Na2SO4 and evaporated. The resulting orange oil was dissolved in 600 ml of DMSO, then 70 g (1.25 mol) of KOH and 88 g (0.62 mol) of MeI were added to the resulting solution. This mixture was stirred for 3 h at ambient temperature. Further on, the solution was decanted from an excess of KOH, the latter was washed with 2×200 ml of dichloromethane, and 2000 cm3 of water was added to the combined solution. The organic layer was separated, and the aqueous layer was additionally extracted with 2×100 ml of dichloromethane. The combined organic extract was additionally washed with 5×1500 ml of water, dried over Na2SO4, and evaporated to dryness. Fractional distillation of the residue in vacuum gave 72.3 g (92%) of 7-bromo-1-methoxy-2,4-dimethylindane, b.p. 107-112° C./5 mm Hg.
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