تفاعل #155422

معادلة التفاعل

4-hydroxybenzaldehyde

tetrahydro-pyran-4-carboxylic acid

thionyl chloride

pyridine

→

4-formylphenyl tetrahydro-2H-pyran-4-carboxylate

المردود 87.4%

المذيبات

water

CH2Cl2

ظروف التفاعل

المعالجة

1. 1
   أخرىTo a 100 mL dry round bottom flask
2. 2
   درجة الحرارةThe mixture was refluxed for 45 minutes
3. 3
   أخرىall the volatile materials were rotary-evaporated
4. 4
   workup.ADDITIONTo the residue, anhydrous CH2Cl2 (10 mL) was added
5. 5
   درجة الحرارةwarmed from 0° C. to room temperature slowly
6. 6
   أخرىat room temperature
7. 7
   أخرىovernight
8. 8
   أخرىthe CH2Cl2 layer was separated
9. 9
   استخلاصThe aqueous layer was extracted continually with CH2Cl2 (50 mL×3)
10. 10
    غسيلThe combined CH2Cl2 solution was washed with a cold aqueous solution of saturated NaHCO3 (80 mL)
11. 11
    أخرىAfter drying
12. 12
    أخرىremoval of the solvent
13. 13
    أخرىthe residue was purified with a silica gel chromatography (heptane/ethyl acetate, gradient eluting)

الإجراء التجريبي

To a 100 mL dry round bottom flask were added tetrahydro-pyran-4-carboxylic acid (2.8 g, 21.5 mmol), thionyl chloride (2.8 mL, 34.4 mmol). The mixture was refluxed for 45 minutes, then all the volatile materials were rotary-evaporated. To the residue, anhydrous CH2Cl2 (10 mL) was added. The resulting solution was cooled to 0° C., and pyridine (2.63 g, 21.5 mmol) was added, followed by a solution of 4-hydroxybenzaldehyde (2.04 g, 25.8 mmol) in anhydrous CH2Cl2 (30 mL). The reaction mixture was stirred and warmed from 0° C. to room temperature slowly, then at room temperature overnight. To the reaction mixture, water (60 mL) was added and the CH2Cl2 layer was separated. The aqueous layer was extracted continually with CH2Cl2 (50 mL×3). The combined CH2Cl2 solution was washed with a cold aqueous solution of saturated NaHCO3 (80 mL). After drying and removal of the solvent, the residue was purified with a silica gel chromatography (heptane/ethyl acetate, gradient eluting) to give 4-formylphenyl tetrahydro-2H-pyran-4-carboxylate (4.40 g) as colorless oil. Yield: 87%. 1H NMR (CDCl3, 300 MHz): δ=9.97 (s, 1H), 7.91 (d, J=8.7 Hz, 2H), 7.27 (d, J=8.4 Hz, 2H), 4.06-4.00 (m, 2H), 3.55-3.47 (m, 2H), 2.88-2.81 (m, 1H), 2.03-1.88 (m, 4H). 13C NMR (CDCl3, 75.5 MHz): δ=190.9, 172.2, 155.3, 133.9, 131.1, 122.2, 115.9, 66.8, 40.1, 28.4.

المصدر