Reaktion #4891

Reaktionsgleichung

sodium hypobromite

bromine

sodium hydroxide

hydrochloric acid

2-hydroxy-nicotinic acid

sodium hydroxide

sodium hypobromite

→

product

Ausbeute 63.5%

5-Bromo-2-hydroxy-3-pyridinecarboxylic acid

Ausbeute 63.5%

Lösungsmittel

water

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeprepared
2. 2
   workup.ADDITIONdiluted to 400 ml
3. 3
   workup.STIRRINGthe reaction solution was stirred for another 24 hr
4. 4
   TemperaturThe reaction solution was cooled in an ice bath
5. 5
   SonstigeCrystallization from isopropyl alcohol

Vorschrift

To a solution of 10 g (0.07 mole) of 2-hydroxy-nicotinic acid in 16.8 g of 50% sodium hydroxide (0.21 mole) diluted with 25 ml of water was added 200 ml of sodium hypobromite solution prepared by adding 13.6 g (0.17 mole) of bromine to a solution of 20.16 g of 50% sodium hydroxide (0.25 mole) in 125 ml of water at 0° C. diluted to 400 ml. After 24 hrs of stirring at room temperature, another 100 ml portion of the above sodium hypobromite solution was added and the reaction solution was stirred for another 24 hr. The reaction solution was cooled in an ice bath and acidified carefully with 12N hydrochloric acid. Crystallization from isopropyl alcohol gave 9.7 g (63.5%) of product. A sample was further recrystallized from 95% ethanol, m.p. 245° C.

Quelle