3-Chloro-5-(trifluoromethyl)benzene-1,2-diamine → 5-chloro-7-trifluoromethyl-3-aminoquinoxalin-2(1H)-one

HRID 235301Notes

Reaction equation

[Cl:1][C:2]1[C:3]([NH2:13])=[C:4]([NH2:12])[CH:5]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:7]=1.[C:14]([O:19]CC)(=S)[C:15]([NH2:17])=O>C(O)CCC>[Cl:1][C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:5]=[C:4]2[C:3]=1[N:13]=[C:15]([NH2:17])[C:14](=[O:19])[NH:12]2

Participants

Conditions

Temperature: 25 °C

Procedure

An adaptation of the method of Burrell et al., J. Chem. Soc. Perkin I. 2707 (1973), was used. A mixture of 3-chloro-5-trifluoromethyl-1,2-phenylenediamine (420 mg, 2.00 mmol; Maybridge Co.) and ethyl thiooxamate (293 mg, 2.20 mmol; Aldrich Co.) in 4 mL of 1-butanol was heated to reflux. The resulting solution was stirred under reflux for 6 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 50 mg (9.5%) of 5-chloro-7-trifluoromethyl-3-aminoquinoxalin-2(1H)-one (tentatively named as this since the regiochemistry is not sure) as a pale yellow solid: mp 270°-272° C. 1H NMR (300 MHz, DMSO-d6) δ 12.043 (br s, 1H, NH), 7.561 (s, 1H, H-7), 7.463 (s, 1H, H-5). LRMS: 263 (M+, 100%), 235 (50%).

Workup

temperaturewas heated to reflux
temperatureunder reflux for 6 h
filtrationfiltered
washthe solid was washed with EtOH (5×2 mL)
customdried in vacuum at 60° C. overnight

Sources & evidence

ORD record: ord-b662409104534fd185339cd12c93072f
Source dataset: uspto-grants-1997_01
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05597922

Reaction notes

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