Dichloroacetic Acid → HCID 21163197, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 19.33 g of dichloroacetic acid in 200 ml of anhydrous dioxane was added dropwise at room temperature with stirring to a mixture of 16.8 g of sodium hydride in a 50% oil suspension, 150 ml of anhydrous dioxane and 1.6 g of dibenzo-18-courone-6 and then a solution of 31.7 g of 5-chloro-2-hydroxy-α-methyl-α-(3-trifluoromethylphenyl)-benzene-methanol in 200 ml of dioxane was added thereto dropwise. The mixture was progressively heated to 80° C. and was held there for 5 hours and then was cooled. The mixture was poured into ice and the aqueous phase was extracted with 400 ml of ether and was then acidified with 30 ml of concentrated hydrochloric acid. The aqueous phase was then extracted 3 times with 350 ml of methylene chloride and the organic extracts were washed twice with 200 ml of water and was extracted 4 times with 250 ml of an aqueous saturated sodium bicarbonate solution. The aqueous phase was washed with 200 ml of ether and was acidified with 80 ml of concentrated hydrochloric acid. The aqueous phase was then extracted 4 times with 200 ml of water and the ether extracts were washed 5 times with 100 ml of water, dried over magnesium sulfate, treated with activated carbon and filtered. The filtrate was evaporated to dryness under reduced pressure to obtain 28.4 g of raw 6-chloro-4-methyl-4-(3-trifluoromethylphenyl)-[4H]-1,3-benzodioxin-2-carboxylic acid (mixture of 2 diastereoisomeric racemates).

Provenance & Evidence