Phosphorodichloridic acid, phenyl ester → 2-Chloro-5-(diphenylmethyl)-pyridine
Reaction equation
[C:1]1([CH:7]([C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[C:8]2[CH:9]=[CH:10][C:11](=O)[NH:12][CH:13]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C1C=CC(OP(Cl)([Cl:30])=O)=CC=1.[OH-].[NH4+]>>[Cl:30][C:11]1[CH:10]=[CH:9][C:8]([CH:7]([C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[C:1]2[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=2)=[CH:13][N:12]=1Participants
4
Procedure
Heat 55 g. of the crude 5-(diphenylmethyl)-2-pyridone and 110 ml. of phenylphosphoric dichloride at 200°-210° with stirring for 6 hours. Pour the cooled reaction mixture onto ice, basify with ammonium hydroxide, extract with ethyl ether, dry the ether extracts, and concentrate to a residue. Distill the residue at 160°-175°/0.15 mm. and crystallize the distillate from hexane to obtain 2-chloro-5-(diphenylmethyl)-pyridine, m.p. 69.5°-71°.