Dimethylformamide → 4-ethoxycarbonylmethyl-7-nitro-2H-1,4-benzoxazin-3(4H)-one
Reaction equation
Br[CH2:2][C:3]([O:5][CH2:6][CH3:7])=[O:4].[NH2:8][C:9]1[CH:14]=[CH:13][C:12]([N+:15]([O-:17])=[O:16])=[CH:11][C:10]=1[OH:18].[C:19](=[O:22])([O-])[O-].[K+].[K+].[CH3:25]N(C)C=O>>[CH2:6]([O:5][C:3]([CH2:2][N:8]1[C:9]2[CH:14]=[CH:13][C:12]([N+:15]([O-:17])=[O:16])=[CH:11][C:10]=2[O:18][CH2:25][C:19]1=[O:22])=[O:4])[CH3:7]Participants
Procedure
Ethyl bromoacetate (92 g) was added dropwise at a temperature of 50° C. to 60° C. to a mixture of 2-amino-5-nitrophenol (38.5 g), potassium carbonate (106.4 g) and N,N-dimethylformamide (100 ml). After the mixture was stirred at a temperature of 100° C. to 110° C. for 6 hours, it was cooled and poured into ice-cold water (500 g). The liquor was extracted twice with toluene (300 ml), both portions of the extraction liquor were combined and washed with water, an aqueous solution of 5% potassium hydroxide, and water, in that order, and dried with anhydrous sodium sulfate, then the solvent was distilled off. Recrystallization of the residue from toluene-hexane gave the desired 4-ethoxycarbonylmethyl-7-nitro-2H-1,4-benzoxazin-3(4H)-one (30 g). When the mother liquor was distilled and recrystallized from ethanol, additional 1.3 g of the desired compound was produced. mp. 120.5°-121.5° C.
Workup
- temperatureit was cooled
- extractionThe liquor was extracted twice with toluene (300 ml)
- washwashed with water
- dry with materialan aqueous solution of 5% potassium hydroxide, and water, in that order, and dried with anhydrous sodium sulfate
- distillationthe solvent was distilled off
- customRecrystallization of the residue from toluene-hexane
Sources & evidence
- ORD record
- ord-b3b748271ca54d61aa51572550ff93d9
- Source dataset
- uspto-grants-1989_01
- Patent number
- US04798620
Reaction notes
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