Dichloromethane → HCID 18980352, compound

To a suspension of cyanoacetic acid (1.70 g, 20 mmol) in CH2Cl2 (50 mL) oxalyl chloride (2.2 mL, 25 mmol) was added. The mixture was stirred for 2 h, more oxalyl chloride (2.2 mL, 25 mmol) was added and the mixture was refluxed while stirring for 3 h. The mixture was cooled to room temperature and evaporated twice with ethanol-free CHCl3 (20 mL) to remove excess of (COCl)2. To the residue was added 4,5-dichloro-2-nitroaniline (1.035 g, 5 mmol) and CH2Cl2 (10 mL) and the resulting mixture was stirred for 3 h, then diluted with ether (50 mL). The precipitate was filtered, washed with ether (5×10 mL) to give 0.891 g (65%) of the title compound as an orange solid: mp 156°-158° C. (from EtOH); IR (KBr) 3369, 3118, 2928, 2261, 1694, 1609, 1576, 1498, 1346 and 1280 cm-1 ; 1H NMR (DMSO-d6) δ4.00 (s, 2H), 7.94 (s, 1H), 8.31 (s, 1H), 10.70 (s, 1H, N--H). HRMS Calcd for C9H5N3O3Cl2 : 272.9708. Found: 272.9712.

1. additionwas added
2. temperaturethe mixture was refluxed
3. stirringwhile stirring for 3 h
4. customevaporated twice with ethanol-free CHCl3 (20 mL)
5. customto remove excess of (COCl)2
6. stirringthe resulting mixture was stirred for 3 h
7. filtrationThe precipitate was filtered
8. washwashed with ether (5×10 mL)

ORD record

ord-7c39629c31f946d697e983696d7b9c2d

Source dataset

uspto-grants-1998_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05801183