Reaktion #213931

Reaktionsgleichung

3-nitro-4-benzyloxyphenylglyoxylic acid

hydrochloric acid

→

3-nitro-4-hydroxyphenylglyoxylic acid

Ausbeute 90.4%

Lösungsmittel

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONTo the reaction mixture was added under cooling ice-water (600 ml.)
2. 2
   Extraktionthe mixture was extracted with ethyl acetate
3. 3
   WaschenThe extract was washed with ice-water
4. 4
   Trocknendried over magnesium sulfate
5. 5
   Einengenconcentrated to dryness under reduced pressure
6. 6
   SonstigeThe residue was recrystallized from a mixture of benzene: ether: petroleum ether (2:1:4)
7. 7
   FiltrationThe crystals were collected by filtration
8. 8
   Waschenwashed with benzene
9. 9
   Sonstigedried under reduced pressure

Vorschrift

A mixture of 3-nitro-4-benzyloxyphenylglyoxylic acid (30 g.), conc. hydrochloric acid (90 ml.) and acetic acid (120 ml.) was stirred for 3 hours at 100° C. To the reaction mixture was added under cooling ice-water (600 ml.) and the mixture was extracted with ethyl acetate. The extract was washed with ice-water, dried over magnesium sulfate and concentrated to dryness under reduced pressure. The residue was recrystallized from a mixture of benzene: ether: petroleum ether (2:1:4). The crystals were collected by filtration, washed with benzene and dried under reduced pressure to give 3-nitro-4-hydroxyphenylglyoxylic acid (19.0 g.), mp 139° to 140.5° C.

Quelle