تفاعل #9002

معادلة التفاعل

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

المردود 28.4%

المذيبات

dichloromethane

ظروف التفاعل

المعالجة

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

الإجراء التجريبي

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).

المصدر