Réaction #2328971

Équation de réaction

6-hydroxy-2-naphthoic acid

2,6-dihydroxynaphthalene

p-toluenesulfonic acid monohydrate

→

6-hydroxynaphthyl 6-hydroxy-2-naphthoate

Rendement 66.0%

Solvants

toluene

Conditions de réaction

Traitement

1. 1
   Températurewas heated
2. 2
   Filtrationfiltered
3. 3
   Filtrationthe solid was finally filtered off

Mode opératoire

A mixture of 9.41 g (0.05 mol) of 6-hydroxy-2-naphthoic acid, 24.03 g (0.15 mol) of 2,6-dihydroxynaphthalene, 0.8 g of p-toluenesulfonic acid monohydrate and 3 drops of concentrated sulfuric acid in 100 ml of toluene was heated under reflux with occasional addition of concentrated sulfuric acid (3 drops every 3 h) for 12 h. The resulting suspension was cooled to room temperature and filtered. The filtercake was suspended in methanol, the suspension was stirred for 3 h and the solid was finally filtered off. 10.9 g of 6-hydroxynaphthyl 6-hydroxy-2-naphthoate (“NpNp”) were obtained as a brownish solid which was processed in the subsequent step without further purification.

Source