Reaktion #9004

Reaktionsgleichung

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

triethylamine

acetic anhydride

→

monoacetate

2-acetoxymethyl-5-hydroxymethyl-N-benzylimidazole

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   WaschenThe reaction was then washed with aqueous ammonium chloride
2. 2
   Sonstigethe layers separated
3. 3
   ExtraktionThe aqueous layer was extracted twice with dichloromethane
4. 4
   TrocknenThe combined organic fractions were then dried over anhydrous sodium sulfate
5. 5
   Einengenconcentrated
6. 6
   SonstigePurification by chromatography on silica gel (5% methanol in dichloromethane)

Vorschrift

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).

Quelle