Reacción #9002

Ecuación de reacción

sodium potassium tartrate

ester

2-(tert-butoxycarbonylamino-methyl)-oxazole-4-carboxylic acid methyl ester

DIBAL-H

→

(4-hydroxymethyl-oxazol-2-ylmethyl)-carbamic acid tert-butyl ester

Rendimiento 28.4%

Disolventes

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.STIRRINGThe mixture was stirred rapidly for 30 minutes (until the aqueous and organic layers
2. 2
   Otrowere then separated
3. 3
   ExtracciónThe aqueous layer was extracted twice with dichloromethane
4. 4
   SecadoThe combined organic fractions were then dried over anhydrous sodium sulfate
5. 5
   Concentraciónconcentrated
6. 6
   OtroPurification by chromatography on silica gel (5% methanol in dichloromethane)

Procedimiento

The ester (178 mg, 0.695 mmol) in 0° C. dichloromethane (8 mL) was treated with DIBAL-H (1 M in dichloromethane, 2.08 mL, 2.08 mmol). The mixture was then stirred at 0° C. for 2 hours before being treated with aqueous 5% sodium potassium tartrate (8 mL). The mixture was stirred rapidly for 30 minutes (until the aqueous and organic layers clarified), and the layers were then 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 (4-hydroxymethyl-oxazol-2-ylmethyl)-carbamic acid tert-butyl ester as an oil (45 mg, 28%). 1H NMR (CDCl3) δ 1.40 (s, 9H), 4.43 (d, 2H, J=5.6 Hz), 4.56 (s, 2H), 5.37 (s, 1H), 7.54 (s, 1H).

Fuente