反应详情

Combine 50 g. (0.174 mole) of the 5-substituted 2-pyridone from step A with 125 ml. of phenylphosphonic dichloride and heat at 210°-220° C. for about 7 hours with stirring. Allow to stand overnight and pour onto ice. Basify with ammonium hydroxide and extract with ethyl ether. Dry the ether solution and concentrate to a residue. Distill the residue and collect the fraction boiling at 205°-215° C. at 0.55 mm. (49 g.).

1. additionpour onto ice
2. extractionBasify with ammonium hydroxide and extract with ethyl ether
3. dry with materialDry the ether solution
4. concentrationconcentrate to a residue
5. distillationDistill the residue
6. customcollect the fraction boiling at 205°-215° C. at 0.55 mm