Réaction #9004

Équation de réaction

2,5-bis-(hydroxymethyl)-N-benzylimidazole

triethylamine

acetic anhydride

→

monoacetate

2-acetoxymethyl-5-hydroxymethyl-N-benzylimidazole

Solvants

dichloromethane

Conditions de réaction

Traitement

1. 1
   LavageThe reaction was then washed with aqueous ammonium chloride
2. 2
   Autrethe layers separated
3. 3
   ExtractionThe aqueous layer was extracted twice with dichloromethane
4. 4
   SéchageThe combined organic fractions were then dried over anhydrous sodium sulfate
5. 5
   Concentrationconcentrated
6. 6
   AutrePurification by chromatography on silica gel (5% methanol in dichloromethane)

Mode opératoire

To a solution of 2,5-bis-(hydroxymethyl)-N-benzylimidazole (436 mg, 2.0 mmol) in dichloromethane (10 mL) was added triethylamine (0.35 mL, 2.0 mmol) and acetic anhydride (0.19 mL, 2.0 mmol). The mixture was then stirred overnight (16 h) at room temperature. The reaction was then washed with aqueous ammonium chloride and the layers separated. The aqueous layer was extracted twice with dichloromethane. The combined organic fractions were then dried over anhydrous sodium sulfate and concentrated. Purification by chromatography on silica gel (5% methanol in dichloromethane) gave the monoacetate, 2-acetoxymethyl-5-hydroxymethyl-N-benzylimidazole, as a white powder (300 mg, 58%). 1H NMR (CDCl3) δ 1.83 (s, 3H), 4.49 (s, 2H), 5.06 (s, 2H), 5.33 (s, 2H), 6.97 (m, 2H), 7.28 (m, 3H).

Source