Triethylamine → (7-Fluoro-1,2,3,4-tetrahydro-2,3-dioxoquinoxalin-1-yl)-methanephosphonic acid diethyl ester
Reaction equation
[CH2:1]([O:3][P:4]([CH2:9][NH:10][C:11]1[CH:16]=[C:15]([F:17])[CH:14]=[CH:13][C:12]=1[NH2:18])(=[O:8])[O:5][CH2:6][CH3:7])[CH3:2].C(N(CC)CC)C.[Cl-].C([O:29][C:30](=O)[C:31](O)=[O:32])C>O1CCCC1>[CH2:1]([O:3][P:4]([CH2:9][N:10]1[C:11]2[C:12](=[CH:13][CH:14]=[C:15]([F:17])[CH:16]=2)[NH:18][C:30](=[O:29])[C:31]1=[O:32])(=[O:8])[O:5][CH2:6][CH3:7])[CH3:2]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
660 mg of N(-2-amino-5-fluorophenyl)-aminomethanephosphonic acid diethyl ester is introduced in 70 ml of absolute tetrahydrofuran with 509 mg of triethylamine. A solution of 685 mg of oxalic acid ethyl ester chloride in 30 ml of tetrahydrofuran is slowly instilled into this solution. The batch is stirred for 4 hours at room temperature. After suctioning-off of the precipitated salts, the filtrate is concentrated by evaporation, boiled in a mixture of 23 ml of ethanol and 23 ml of 1 N hydrochloric acid for 2 hours at 110° C. bath temperature. It is evaporated to dryness and the residue is chromatographed on silica gel with methylene chloride:ethanol=10:1. 561 mg of (7-fluoro-1,2,3,4-tetrahydro-2,3-dioxoquinoxalin-1-yl)-methanephosphonic acid diethyl ester is obtained.
Workup
- concentrationAfter suctioning-off of the precipitated salts, the filtrate is concentrated by evaporation
- additionboiled in a mixture of 23 ml of ethanol and 23 ml of 1 N hydrochloric acid for 2 hours at 110° C. bath temperature
- customIt is evaporated to dryness
- customthe residue is chromatographed on silica gel with methylene chloride
Sources & evidence
- ORD record
- ord-0e19008555514bb5888a7fb46b3d1e50
- Source dataset
- uspto-grants-1999_09
- Patent number
- US05955461
Reaction notes
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