反应 #1620

反应方程式

potassium carbonate

diethyl dibromomalonate

(R)-2-(3,4-dihydroxyphenyl)propylcarbamic acid, t-butyl ester

→

(R)-5-[N-(t-Butyloxycarbonyl)-2-aminopropyl]-1,3-benzodioxole-2,2-dicarboxylic acid, diethyl ester

溶剂

acetone

acetone

反应条件

后处理

1. 1
   温度After cooling to ambient temperature
2. 2
   workup.STIRRINGthe reaction was stirred at ambient temperature for 18 hours
3. 3
   过滤The suspension was filtered
4. 4
   洗涤the residue was washed with ethyl acetate
5. 5
   其他evaporated
6. 6
   其他the residue was partitioned between ethyl acetate (200 ml) and dilute hydrochloric acid (100 ml, pH5)
7. 7
   其他The organic layer was separated
8. 8
   洗涤washed with water (2×100 ml) and brine (100 ml)
9. 9
   干燥dried (MgSO4)
10. 10
    其他evaporated
11. 11
    其他The residue was purified by column chromatography on silica gel eluting with 25% ethyl acetate in n-hexane giving the title compound as an oil

实验过程

A solution of (R)-2-(3,4-dihydroxyphenyl)propylcarbamic acid, t-butyl ester. (1.07 g, 4 mMol) in acetone (25 ml) containing potassium carbonate (3 equiv, 1.66 g, 12 mMol) was stirred at 60° C. under an argon atmosphere for 1 hour. After cooling to ambient temperature, a solution of diethyl dibromomalonate (1.27 g, 4 mMol) in acetone (7 ml) was added and the reaction was stirred at ambient temperature for 18 hours. The suspension was filtered and the residue was washed with ethyl acetate. The filtrates were combined, evaporated and the residue was partitioned between ethyl acetate (200 ml) and dilute hydrochloric acid (100 ml, pH5). The organic layer was separated, washed with water (2×100 ml) and brine (100 ml), dried (MgSO4) and evaporated. The residue was purified by column chromatography on silica gel eluting with 25% ethyl acetate in n-hexane giving the title compound as an oil;

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