Reaktion #157192

Reaktionsgleichung

citric acid

THF

NaOH

1-Benzyloxy-naphthalene-2-carboxylic acid benzyl ester

→

1-Benzyloxy-naphthalene-2-carboxylic Acid

Lösungsmittel

H2O

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONA condenser was added
2. 2
   Temperaturthe mixture was refluxed for 9 hours
3. 3
   workup.ADDITIONwas added to pH-4
4. 4
   ExtraktionExtracted with CH2Cl2 (3×100 mL)
5. 5
   Waschenwashed with H2O (2×150 mL) and saturated NaCl (1×150 mL)
6. 6
   SonstigePurification
7. 7
   Sonstigewas achieved by recrystallization in hexanes (2×20 mL)
8. 8
   SonstigeSolvent removed under pressure
9. 9
   Einengenconcentrated in vacuo

Vorschrift

Method slightly modified, THF (30 mL) instead of MeOH and 5M NaOH (32 mL) were added to the rbf containing compound 1-Benzyloxy-naphthalene-2-carboxylic acid benzyl ester (1.40 g, 3.80 mmol). A condenser was added and the mixture was refluxed for 9 hours. The mixture was diluted with H2O (100 mL) and citric acid (17.70 g, 92.12 mmol) was added to pH-4. Extracted with CH2Cl2 (3×100 mL), washed with H2O (2×150 mL) and saturated NaCl (1×150 mL). NMR showed final product with small percent of starting material. Purification was achieved by recrystallization in hexanes (2×20 mL). Solvent removed under pressure and concentrated in vacuo. Yield: 0.652 g of white crystals (62%). 1H NMR (400 MHz, CDCl3) δ 5.24 (s, 2H), δ 7.43-7.54 (m, 3H), δ 7.61-7.68 (m, 2H), δ 7.75 (d, J=8.7 Hz, 1H), δ 7.93 (dd, J=7.3 Hz, 1 Hz, 1H), δ 8.10 (d, J=8.7 Hz, 1H), δ 8.25 (d, J=7.8 Hz, 1H).

Quelle