반응 #9876

반응 방정식

Triethylamine

glycine ethyl ester hydrochloride

Compound 9a

3(S)-hydroxy-2-methylene-3-phenylpropanoic acid

dicyclohexylcarbodiimide

→

desired product 10a

[[3(S)-hydroxy-2-methylene-1-oxo-3-phenylpropyl]amino]acetic acid ethyl ester

용매

dichloromethane

반응 조건

후처리

1. 1
   온도cooled to 0° C. (ice bath)
2. 2
   workup.STIRRINGwas stirred at room temperature for 17 h
3. 3
   여과The precipitate (dicyclohexylurea and triethylamine hydrochloride) was collected by filtration
4. 4
   세척The filtrate was washed with a 1N aqueous solution of HCl (50 mL), brine (50 mL)
5. 5
   건조dried over sodium sulfate
6. 6
   기타Evaporation of the solvent
7. 7
   기타afforded an oil which
8. 8
   기타was purified by column chromatography (eluent: hexane/EtOAc=6:4)

실험 절차

Triethylamine (3.75 mL, 0.027 mol, 1.2 eq) was added to a suspension of glycine ethyl ester hydrochloride (3.44 g, 0.024 mol, 1.1 eq) in anhydrous dichloromethane (60 mL) (see FIG. 4). The mixture was stirred for 15 min at room temperature and then cooled to 0° C. (ice bath). Compound 9a (4 g, 0.022 mol, 1 eq) and dicyclohexylcarbodiimide (5.09 g, 0.02469 mol, 1.1 eq) were added successively to the reaction mixture which was stirred at room temperature for 17 h. The precipitate (dicyclohexylurea and triethylamine hydrochloride) was collected by filtration. The filtrate was washed with a 1N aqueous solution of HCl (50 mL), brine (50 mL) and dried over sodium sulfate. Evaporation of the solvent afforded an oil which was purified by column chromatography (eluent: hexane/EtOAc=6:4). The desired product 10a was obtained as a yellow oil (3.51 g, 60%). Rf 0.25 (hexane/EtOAc=4:6). 1H NMR δ (CDCl3) 1.25 (t, 3H), 3.63 (s, 1H), 4.02 (m, 2H), 4.17 (q, 2H), 5.49 (s, 1H), 5.58 (d, 1H), 5.96 (s, 1H), 6.86 (s, 1H), 7.65 (m, 5H). [M+H]+ 264.1: tR=2.55 min; purity: 96%.

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