Dichloroacetic Acid → HCID 21163200, compound

Temperature

90 °C

A solution of 17 g of dichloroacetic acid in 180 ml of dioxane was added dropwise with stirring to a suspension of 14.9 g of sodium hydride as 50% oil suspension, 1.1 g of dibenzo-18-courone-6 and 160 ml of dioxane and then a solution of 21.5 g of the product of Step A in 220 ml of dioxane was added. The reaction mixture was heated at 90° C. for 3 hours, was cooled and was poured into ice. The aqueous phase was washed with 300 ml of ether, was acidified with 30 ml of concentrated hydrochloric acid and was extracted 3 times with 200 ml of ether. The ether phase was washed twice with 100 ml of water and was extracted twice with 250 ml of aqueous 5% sodium bicarbonate solution. The aqueous phase was washed with 100 ml of ether, acidified with 40 ml of concentrated hydrochloric acid and was extracted 3 times with 250 ml of ether. The combined organic phases were washed with water until the water was neutral, dried over magnesium sulfate and evaporated under reduced pressure to obtain 29.8 g of raw 6-methoxy-4-methyl-4-phenyl-[4H]-1,3-benzodioxin-2-carboxylic acid (mixture of 2 diastereoisomeric racemates).

1. temperaturewas cooled
2. additionwas poured into ice
3. washThe aqueous phase was washed with 300 ml of ether
4. extractionwas extracted 3 times with 200 ml of ether
5. washThe ether phase was washed twice with 100 ml of water
6. extractionwas extracted twice with 250 ml of aqueous 5% sodium bicarbonate solution
7. washThe aqueous phase was washed with 100 ml of ether
8. extractionwas extracted 3 times with 250 ml of ether
9. washThe combined organic phases were washed with water until the water
10. dry with materialdried over magnesium sulfate
11. customevaporated under reduced pressure

ORD record

ord-9cbd36a98d66414a8c0a24f88b80ced2

Source dataset

uspto-grants-1981_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04281012