Reaktion #62738

Reaktionsgleichung

Methyl 3,4-dimethoxy-5-hydroxybenzoate

propargyl chloride

potassium carbonate

→

methyl 3,4-dimethoxy-5-(2-propynyloxy)benzoate

Ausbeute 49.0%

Lösungsmittel

acetone

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled
2. 2
   Filtrationfiltered
3. 3
   Einengenconcentrated
4. 4
   workup.DISSOLUTIONThe resulting oil was dissolved in ethyl acetate (20 mL)
5. 5
   Waschenwashed with water (3×10 mL)
6. 6
   TrocknenThe organic layer was dried (Na2SO4)
7. 7
   Einengenconcentrated

Vorschrift

Methyl 3,4-dimethoxy-5-hydroxybenzoate (E. Spath and H. Roder, Mon. f. Chem. 1922, 43, 93; G. J. Kapadia, Y. N. Vaishnav, M. B. E. Fayez, J. Pharm. Sci. 1969, 9, 1157) (0.54 g, 2.54 mmol), propargyl chloride (0.23 g, 3.04 mmol), sodium iodide (3 mg, 0.02 mmol) and potassium carbonate (0.53 g, 3.81 mmol) were refluxed in acetone (10 mL) for 18 hr, cooled, filtered and concentrated. The resulting oil was dissolved in ethyl acetate (20 mL) and washed with water (3×10 mL). The organic layer was dried (Na2SO4), concentrated and recrystllized from alcohol (2.5 mL)/hexane (20 mL) to give methyl 3,4-dimethoxy-5-(2-propynyloxy)benzoate (0.29 g, 49%); mp 72°-73.5°. Anal. Calcd for C13H14O5 : C, 62.39; H, 5.64. Found: C, 62.28; H, 5.68.

Quelle