Acetic Acid → HCID 13834403, compound

In 135 ml of tetrahydrofuran was dissolved 3.03 g of a 3,5-dinitrobenzoyl derivative of (-)-3-acetoxymethyl-7,8-difluoro-2,3-dihydro-4H-[1,4]benzoxazine, and 135 ml of ethanol and 30 ml of 1.0N potassium hydroxide were added to the solution. After the reaction mixture was stirred at room temperature for 30 minutes, 3 ml of acetic acid was added thereto for neutralization. The mixture was concentrated under reduced pressure, and the concentrate was dissolved in 400 ml of chloroform, washed successively with a sodium bicarbonate aqueous solution and water, dried over anhydrous sodium sulfate and concentrated to dryness under reduced pressure. The solid was subjected to column chromatography using 40 g of silica gel and eluted with chloroform/methanol (50/1 by volume) to obtain 1.17 g of (-)-7,8-difluoro-2,3-dihydro-3-hydroxymethyl-4H-[1,4]benzoxazine.

1. additionwere added to the solution
2. concentrationThe mixture was concentrated under reduced pressure
3. dissolutionthe concentrate was dissolved in 400 ml of chloroform
4. washwashed successively with a sodium bicarbonate aqueous solution and water
5. dry with materialdried over anhydrous sodium sulfate
6. concentrationconcentrated to dryness under reduced pressure
7. washeluted with chloroform/methanol (50/1 by volume)

ORD record

ord-504d18bf82c0497ab498b2866c0f975c

Source dataset

uspto-grants-1992_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05142046