Dichloromethane → 5,6,7,8-Tetrahydro-5,5,8,8-tetramethyl-benz[f]indan-2-one

Participants

Reaction Conditions

Reaction Steps

A 1 L 3-neck flask was charged with AlCl3 (80.8 g, 0.606 mol), fitted with a mechanical stirrer, and a 250 mL addition funnel, charged with anhydrous methylene chloride (370 mL). The slurry was cooled to −20° C. and stirred. The addition funnel was then charged (in two portions over the course of the reaction) with a solution of 2-indanone (40.0 g, 0.303 mol) {Note: Aldrich brand 2-indanone was rinsed with ether to remove brown impurities}, 2,5-dichloro, 2,5-dimethylhexane (55.4 g, 0.303 mol) and anhydrous methylene chloride (180 mL). The solution was dripped onto the cold, stirring AlCl3 slurry over the course of 50 min. After stirring for 2.5 h after the addition was complete, a solution of 2,5-dichloro, 2,5-dimethylhexane (13 g, 0.071 mol) and anhydrous methylene chloride (42 mL). After stirring an additional hour, the reaction mixture was poured onto ice (1 L) and treated with ether (500 mL). The organic layer was separated and the aqueous layer extracted with ether (2×200 mL). The combined organic layers were washed with 2.5 M NaCl (aq) (3×75 mL) then water (25 mL) then dried over MgSO4. The dried organic solution was filtered into a 3 L flask and the solvent was slowly removed with a nitrogen blowing over the surface of the solution. The solid that remained was washed with cold pentane and the solids isolated by filtration. The product, a fine crystalline material, was separated manually from a small amount of chunky oily solids that contained product and an impurity. Yield 21 g.

Provenance & Evidence