Hydrochloric Acid → 5-tert-butyl-6-methoxy-2-methyl-7-phenyl-1H-indene

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Reaction Conditions

Reaction Steps

To a solution of 44.3 g (0.144 mmol) of 6-tert-butyl-5-methoxy-2-methyl-4-phenylindan-1-one in 150 ml of THF cooled to 5° C. 2.72 g (71.9 mmol) of NaBH4 was added. Further on, 75 ml of methanol was added dropwise to this mixture by vigorous stirring for 1 h at 5° C. The resulting mixture was stirred additionally 1 h at 5° C., then 0.5 h at room temperature, and then added to 1 liter of cold water and 30 ml of 12 M HCl in separating funnel. The crude product was extracted consequentially with 250, 100 and 50 ml of dichloromethane, and the combined organic extract was evaporated to dryness. To a solution of the residue in 500 ml of toluene 1.0 g of TsOH was added, this mixture was refluxed with Dean-Stark head for 10 min and then cooled to room temperature using water bath. The resulting solution was washed by aqueous K2CO3 (20 g K2CO3 in 200 ml of H2O), the organic layer was separated, the aqueous layer was extracted with 2×50 ml of dichloromethane. The combined organic solution was dried over K2CO3 and then passed through short layer of silica gel 60 (40-63 um, ca. 10 g). The silica gel layer was additionally washed by 50 ml of dichloromethane. The combined organic elute was evaporated to dryness. This procedure gave 42.0 g (˜100%) of yellowish oil which was further used without an additional purification.

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