Phosphorus oxychloride → HCID 632909, compound
Reaction equation
[Br:1][C:2]1[C:3]([NH:11][C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][C:13]=2[Br:18])=[C:4]([CH:8]=[CH:9][CH:10]=1)[C:5](O)=O.P(Cl)(Cl)([Cl:21])=O>>[Br:1][C:2]1[C:3]2[C:4](=[C:5]([Cl:21])[C:17]3[C:12]([N:11]=2)=[C:13]([Br:18])[CH:14]=[CH:15][CH:16]=3)[CH:8]=[CH:9][CH:10]=1Participants
3
Procedure
A suspension of 7.43 g (20.0 mmol) of 3-bromo-2-(2-bromophenylamino)benzoic acid (XXII) in 19.5 ml (213 mmol) of distilled phosphoryl chloride was heated to reflux for 2.5 h. Subsequently, the excess phosphoryl chloride was distilled off at room temperature under vacuum. The resulting brown oil was dissolved in chloroform, and the solution was added dropwise to ice-cooled diluted aqueous ammonia with stirring. After the mixture had reached room temperature, the phases were separated. The aqueous phase was extracted twice with chloroform, and the combined organic phases were dried over sodium sulfate. The solvent was distilled off under vacuum, and the residue was dried under high vacuum. Fractional sublimation of 7.00 g of raw product under high vacuum yielded 5.5 g (74% of theory) of 4,5-dibromo-9-chloroacridine (XXIII) as an analytically pure yellow solid with a melting point of 195-196° C.