Methanol → 5-t-Butyl-6-methoxy-2-methyl-7-(4-t-butylphenyl)-1h-indene

Participants

Reaction Conditions

Reaction Steps

To a solution of 28.9 g (79.2 mmol) of 6-tert-butyl-4-(4-tert-butylphenyl)-5-methoxy-2-methylindan-1-one in 400 ml of THF cooled to 5° C. 5.00 g (132 mmol) of NaBH4 was added. Further on, 100 ml of methanol was added dropwise to this mixture by vigorous stirring for ca. 7 h at 5° C. The resulting mixture was evaporated to dryness, and the residue wad partitioned between 500 ml of dichloromethane and 1000 ml of 0.5 M HCl. The organic layer was separated, the aqueous layer was additionally extracted with 100 ml of dichloromethane. The combined organic extract was evaporated to dryness to give a colorless oil. To a solution of this oil in 500 ml of toluene 1.0 g of TsOH was added. The formed mixture was refluxed with Dean-Stark head for 15 min and then cooled to room temperature using water bath. The resulting reddish solution was washed by 10% aqueous Na2CO3, the organic layer was separated, the aqueous layer was extracted with 2×100 ml of dichloromethane. The combined organic extract was dried over K2CO3 and then passed through short pad of silica gel 60 (40-63 um). The silica gel pad was additionally washed by 50 ml of dichloromethane. The combined organic elute was evaporated to dryness to give a yellowish crystalline mass. The product was isolated by re-crystallization of this mass from 150 ml of hot n-hexane. Crystals precipitated at 5° C. were collected dried in vacuum. This procedure gave 23.8 g of white macrocrystalline 5-tert-butyl-7-(4-tert-butylphenyl)-6-methoxy-2-methyl-1H-indene. The mother liquor was evaporated to dryness and the residue was recrystallized from 20 ml of hot n-hexane in the same way. This procedure gave additional 2.28 g of the product. Thus, the total yield of the title product was 26.1 g (95%).

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