Dicyclohexylcarbodiimide → Ethyl (2S,3S)-3-[[1-(S)-[alpha-(R)-hydroxybenzyl]-3-methyl-butyl]carbamoyl]oxirane-2-carboxylate

Temperatur

5 °C

To a solution of (2S,3S)-3-ethoxycarbonyloxirane-2-carboxylic acid (696 mg, 4.78 mmol.) in ethyl acetate (15 mL) was added N-hydroxysuccinimide (550 mg, 4.78 mmol.) and then added N,N′-dicyclohexylcarbodiimide (986 mg, 4.78 mmol.) under chilling with ice. The resulting mixture was stirred at 5° C. for one hour, and to the mixture was added (1R,2S)-2-amino-4-methyl-1-phenyl-1-pentanol (1.01 g, 5.23 mmol.). The mixture was stirred overnight at room temperature for one hour. The resulting insoluble material was removed by filtration, and the filtrate was washed successively with 2N hydrochloric acid, water, an aqueous saturated sodium hydrogen carbonate solution, and an aqueous saturated sodium chloride solution, and then dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by middle pressure silica gel column chromatography (n-hexane/ethyl acetate=1/1), to give the desired compound as a white crystalline product (1.29 g, yield: 89%).

1. stirringThe mixture was stirred overnight at room temperature for one hour
2. customThe resulting insoluble material was removed by filtration
3. washthe filtrate was washed successively with 2N hydrochloric acid, water
4. dry with materialan aqueous saturated sodium hydrogen carbonate solution, and an aqueous saturated sodium chloride solution, and then dried over anhydrous sodium sulfate
5. distillationThe solvent was distilled off under reduced pressure
6. customthe residue was purified by middle pressure silica gel column chromatography (n-hexane/ethyl acetate=1/1)

ORD-Eintrag

ord-74ba2b32110a4f46b640f9aee2a0a763

Quelldatensatz

uspto-grants-2002_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06387908B1