반응 #1725971

반응 방정식

6-benzyloxy-1-hydroxy-1,2,3,4-tetrahydro-2-naphthoic acid

sodium hydroxide

→

7-benzyloxy-1,2-dihydro-3-naphthoic acid

수율 79.8%

용매

methanol

반응 조건

후처리

1. 1
   workup.WAITthe mixture is left
2. 2
   농축The resultant is concentrated under reduced pressure
3. 3
   workup.ADDITIONThe concentrate is diluted with water (50 ml)
4. 4
   여과The precipitating crystals are collected by filtration
5. 5
   workup.DISSOLUTIONThis product is dissolved in a mixture of dioxane (50 ml) and concentrated hydrochloric acid (2 ml)
6. 6
   workup.WAITThe mixture is left
7. 7
   workup.WAITstanding for 5 minutes at 80° C.
8. 8
   workup.WAITfor 30 minutes at room temperature
9. 9
   농축The resultant is concentrated under reduced pressure
10. 10
    workup.ADDITIONWater (50 ml) is added to the concentrate
11. 11
    여과The precipitating crystals are collected by filtration

실험 절차

Methyl ester of 6-benzyloxy-1-hydroxy-1,2,3,4-tetrahydro-2-naphthoic acid (0.6 g) is dissolved in methanol (50 ml). To the solution is added an aqueous solution (10 ml) of sodium hydroxide (2 g), and the mixture is left standing for 30 minutes at room temperature. The resultant is concentrated under reduced pressure. The concentrate is diluted with water (50 ml). The precipitating crystals are collected by filtration. This product is dissolved in a mixture of dioxane (50 ml) and concentrated hydrochloric acid (2 ml). The mixture is left standing for 5 minutes at 80° C. and then for 30 minutes at room temperature. The resultant is concentrated under reduced pressure. Water (50 ml) is added to the concentrate. The precipitating crystals are collected by filtration to give 7-benzyloxy-1,2-dihydro-3-naphthoic acid (0.45 g) as colorless crystals, followed by recrystallization from a mixture of methanol and acetone to afford colorless needles, m.p. 202°-205° C.

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