Reaktion #2267060

Reaktionsgleichung

6-hydroxy-2-naphthoic acid

NaOCl

sodium metabisulfite

HCl

4-hydroxybenzoic acid

NaI

NaOH

→

5-iodo-6-hydroxy-2-naphthoic acid

Lösungsmittel

MeOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added dropwise over 75 min
2. 2
   Extraktionextracted with 40 ml of ether
3. 3
   WaschenThe organic layer was washed with brine
4. 4
   Trocknendried over MgSO4
5. 5
   EinengenThe solution was concentrated to an off-white solid, that
6. 6
   Sonstigewas recrystallized from toluene/CH3OH

Vorschrift

Mono-iodination of 6-hydroxy-2-naphthoic acid and 4-hydroxybenzoic acid was carried out following the procedure of Edgar and Falling (J. Org. Chem. 55, 5287, 1990). Thus, 0.75 gm of (4.34 mmol) was dissolved in 19 ml of MeOH and 1.04 gm of NaI (and 0.27 gm of NaOH was added. The solution was cooled to O▪C and aqueous NaOCl (4% solution, 12.9 ml) was added dropwise over 75 min. The resulting mixture was stirred for 1 hr at 0° C. and then treated with 7 ml of 10% aqueous sodium metabisulfite. The mixture was adjusted to pH 7 using 5% HCl and extracted with 40 ml of ether. The organic layer was washed with brine and dried over MgSO4. The solution was concentrated to an off-white solid, that was recrystallized from toluene/CH3OH to provide 0.42 gm of 5-iodo-6-hydroxy-2-naphthoic acid. Reaction of 6′-Tostylatractviloside with 1.2-ethylenediamine

Quelle