Phosphorus oxychloride → HCID 178469510, compound
Reaction equation
C(O[C:4](=[O:19])[C:5](=[CH:11][NH:12][C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)[C:6]([O:8][CH2:9][CH3:10])=[O:7])C.P(Cl)(Cl)(Cl)=O>>[CH2:9]([O:8][C:6]([C:5]1[CH:11]=[N:12][C:13]2[C:14]([C:4]=1[OH:19])=[CH:15][CH:16]=[CH:17][CH:18]=2)=[O:7])[CH3:10]Participants
3
Conditions
- Temperature
- 70 °C
Procedure
A 1 L three-necked flask fitted with a mechanical stirrer was charged with 2-phenylaminomethylene-malonic acid diethyl ester (26.3 g, 0.1 mol), polyphosphoric acid (270 g) and phosphoryl chloride (750 g). The mixture was heated to about 70° C. and stirred for 4 h. The mixture was cooled to room temperature, and filtered. The residue was treated with aqueous Na2CO3 solution, filtered, washed with water and dried. 4-Hydroxyquinoline-3-carboxylic acid ethyl ester was obtained as a pale brown solid (15.2 g, 70%). The crude product was used in next step without further purification.