Sulfuric Acid → HCID 58444074, compound

Participants

Reaction Conditions

Reaction Steps

24.0 g of crude 4-(4-tert-butyl-phenyl)-2-[(1-ethylcyclohexyl)methyl]indan-1-one (˜82% purity), 2.4 g (63.4 mmol) of NaBH4 and 60 ml of toluene are charged in a flask equipped with reflux condenser, dropping funnel and magnetic stirring bar. The mixture is warmed to 50° C. and 12 ml of methanol are slowly added with stirring and stirring is continued for 2.5 h to ensure a complete reaction. Excess NaBH4 is carefully hydrolyzed with approx. 35 ml of 2n H2SO4. The organic phase is separated and the water phase is washed with another 30 ml of toluene. The combined organic phases are twice extracted with 2n H2SO4 and dried over anhydrous MgSO4. Most of the solvent is removed in a vacuum and replaced by fresh toluene up to a total volume of 90 ml and 0.26 g of p-toluenesulfonic acid are added. The reaction flask is fitted with a water separator and the reaction mixture is heated to reflux for 1.5 h. The conversion can be monitored by TLC. Once the dehydration is complete, the solution is washed with a saturated NaHCO3 solution and dried over anhydrous MgSO4. The solvent is thoroughly removed in a vacuum and 22.4 g of a brown oil is obtained. Purification of the indene is carried out via a column chromatography. Yield: 15.3 g (˜81%) of 7-(4-tert-Butyl-phenyl)-2-[(1-ethylcyclohexyl)methyl]-1H-indene.

Provenance & Evidence