反应详情

2-(3-Hydroxyphenyl)glyoxylic acid (3.32 g.) and 1 N-methanol solution of hydroxylamine (45 ml.) were refluxed with stirring for 25 minutes. The reaction mixture was concentrated under reduced pressure. The residue was dissolved in 1 N-aqueous solution of sodium hydroxide (70 ml.). An aqueous solution was washed with ether, acidified with dil. hydrochloric acid and then extracted with ethyl acetate. The extract was washed, dried and treated with an activated charcoal. The solvent was distilled off to give 2-hydroxyimino-2-(3-hydroxyphenyl)acetic acid (a mixture of syn and anti isomers) (2.9 g.).

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. dissolutionThe residue was dissolved in 1 N-aqueous solution of sodium hydroxide (70 ml.)
3. washAn aqueous solution was washed with ether
4. extractionextracted with ethyl acetate
5. washThe extract was washed
6. customdried
7. additiontreated with an activated charcoal
8. distillationThe solvent was distilled off