반응 #48627
ord-90f47e08bb984cd5a0e1a8455c23aa0d
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후처리
- 1농축concentrate
- 2workup.STIRRINGstir overnight at 65° C
- 3기타quench with water (300 mL)
- 4세척wash with water, and saturated aqueous sodium chloride
- 5추출Extract the aqueous washes with ethyl acetate
- 6건조dry (magnesium sulfate)
- 7여과filter
- 8기타purify twice
- 9세척(silica gel chromatography, eluting with 5:95 to 10:90 ethyl acetate:hexanes)
실험 절차
Add tricaprylmethylammonium chloride (Aliquat® 336) (4.5 g, 11.2 mmol) and tetrabutylammonium bromide (TBAB) (5.7 g, 15.7 mmol) to a solution of 4-(R)-[2-(S)-amino-1-(S)-hydroxy-3-(3-hydroxyphenyl)-propyl]-2,2-dimethyloxazolidine-3-carboxylic acid tert-butyl ester (16.45 g, crude) in tetrahydrofuran (200 mL). Add portionwise 95% sodium hydride (2.6 g, 90 mmol) and stir for 10 minutes. Add benzyl bromide (13.4 mL, 112.5 mmol) and heat at 60° C. for 40 minutes and concentrate. Add more 95% sodium hydride (5.4 g, 225 mmol) and benzyl bromide (27 mL, 225 mmol) in tetrahydrofuran (−5 mL) and stir overnight at 65° C. Dilute with ethyl acetate, quench with water (300 mL), wash with water, and saturated aqueous sodium chloride. Extract the aqueous washes with ethyl acetate, comvine the organic layers, dry (magnesium sulfate), filter and purify twice (silica gel chromatography, eluting with 5:95 to 10:90 ethyl acetate:hexanes) to give the desired compound as an orange residue (16.01 g, 49%).