Reaktion #2160083

Reaktionsgleichung

sodium chlorite

2,6-dimethoxy-1-naphthalenecarboxaldehyde

resorcinol

→

2,6-dimethoxy-1-naphthalenecarboxylic acid

Ausbeute 84.0%

Lösungsmittel

water

tert-butanol

p-dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto cool
2. 2
   Einengenthe mixture was concentrated under vacuum
3. 3
   SonstigeThe residue was partitioned between 1M KOH and dichloromethane
4. 4
   SonstigeThe phases were separated
5. 5
   Waschenwashed three times with dichloromethane
6. 6
   Waschenwashed with water
7. 7
   Trocknenwith saturated sodium chloride and then dried over Na2SO4
8. 8
   FiltrationAfter filtration and concentration
9. 9
   Sonstigethe residue was recrystallized from ethanol-water

Vorschrift

A solution of sodium chlorite (15.7 g, 80%, 0.139 mol) in 45 mL of water was added rapidly to a warm solution of 2,6-dimethoxy-1-naphthalenecarboxaldehyde [25.76 g, 0.119 mol, described by N. P. Buu-Hoi et al, J. Chem. Soc., 2776 (1955)], resorcinol (17.8 g, 0.162 mol) and acetic acid (0.25 g) in tert-butanol (115 mL) and p-dioxane (95 mL). The reaction temperature was maintained at about 85° C. for 10 minutes then allowed to cool and the mixture was concentrated under vacuum. The residue was partitioned between 1M KOH and dichloromethane. The phases were separated and the aqueous solution was acidified with 6N HCl and washed three times with dichloromethane. The acidic dichloromethane extracts were combined and washed with water and then with saturated sodium chloride and then dried over Na2SO4. After filtration and concentration, the residue was recrystallized from ethanol-water to give 23.1 g (84% yield) of 2,6-dimethoxy-1-naphthalenecarboxylic acid as an off-white solid, m.p. 153°-155° C.

Quelle