Calcium Carbonate → HCID 9820740, compound

Participants

Reaction Steps

To a suspension of 2,3-dihydro-5-hydroxy-6,7-dimethyl-4-(2-methyl-2-propenyl)-1H-indole-1-carbaldehyde (4.91 g, 20.0 mmol) in dichloromethane (10 mL) and methanol (20 mL) was added calcium carbonate (2.60 g, 26.0 mmol), the mixture was ice-cooled, a solution of benzyltrimethylammonium dichloroiodate (7.66 g, 22.0 mmol) in dichloromethane (20 mL) was added dropwise over 10 minutes under nitrogen atmosphere, and the mixture was stirred at room temperature for 30 minutes. The reaction mixture was filtered, and concentrated under reduced pressure. To the residue was added a solution of sodium hydrogen sulfite (2.50 g) in water (50 mL), and the mixture was extracted with ethyl acetate three times. The combined organic layers were washed with water and saturated brine, dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (hexane-ethyl acetate 5;1 then 2:1), and recrystallized from ethyl acetate-diisopropyl ether to obtain 4.34 g of the title compound.

Provenance & Evidence