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177944-77-3

2,3-Quinoxalinedione,1,4-dihydro-,monooxime(9CI) synthesis

3synthesis methods
Ethanethioic acid, 2-amino-2-oxo-, S-ethyl ester

51216-90-1
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35015-91-9 Synthesis
3-AMINO-QUINOXALINE-2-OL

35015-91-9
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2,3-Quinoxalinedione,1,4-dihydro-,monooxime(9CI)

177944-77-3
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Yield:177944-77-3 85 mg (18%)

Reaction Conditions:

in ethanol;

Steps:

51 Preparation of 3-(Hydroxyimino)-1,4-dihydroquinoxalin-2-one

Example 51 Preparation of 3-(Hydroxyimino)-1,4-dihydroquinoxalin-2-one 3-Aminoquinoxalin-2(1H)-one. An adaptation of the method of Burrell et al., J. Chem. Soc. Perkin I. 2707 (1973), was used. A mixture of 1,2-phenylenediamine (324 mg, 3.00 mmol; Aldrich Co.) and ethyl thiooxamate (400 mg, 3.00 mmol; Aldrich Co.) in 7.5 mL of ethanol was heated to reflux. The resulting solution was stirred under reflux for 3 h. The resulting suspension was cool to 25° C. A pale yellow precipitate appeared. The mixture was vacuum filtered and the solid was washed with EtOH (5*2 mL) and dried in vacuum at 60° C. overnight to yield 85 mg (18%) of 3-aminoquinoxalin-2(1H)-one as a pale yellow solid (McKillop et al., Tetrahedron Lett. 23:3357 (1982)): mp dec.>320° C. 1 H NMR (300 MHz, DMSO-d6) δ 7.261-7.075 (m, 4H, H-5+H-6+H-7+H-8). LRMS: 161 (M+, 100%), 133 (50%).

References:

US5597922,1997,A