Reaction #2267060

Reaction equation

6-hydroxy-2-naphthoic acid

NaOCl

sodium metabisulfite

HCl

4-hydroxybenzoic acid

NaI

NaOH

→

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

Solvents

MeOH

Conditions

Workup

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

Procedure

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

Source