Diisobutylaluminum hydride → (S)-tert-butyl 4-((R)-5-hydroxy-2-(tosyloxymethyl)pentyl)-2,2-dimethyloxazolidine-3-carboxylate

温度

0 °C

To a solution of (S)-tert-butyl 4-((R)-5-tert-butoxy-5-oxo-2-(tosyloxymethyl)pentyl)-2,2-dimethyloxazolidine-3-carboxylate (317 mg, 0.58 mmol) in anhydrous DCM (8 mL) at −78° C. under N2 was added DiBAlH (1M in hexane, 1.75 mL, 1.75 mmol) dropwise. After the addition, the reaction mixture was stirred for another 30 min. The reaction was quenched with MeOH (2 mL), followed by 50% Rochelle's salt aq solution and stirred 2 hr. The resulting solution was extracted with DCM (3×20 mL), the combined organic phases were concentrated and dissolved in THF/MeOH (10 mL, 4/1, v/v), and chilled to 0° C., NaBH4 (11 mg, 0.29 mmol) was added and stirred at this temperature for 30 min. The reaction was quenched by aqueous NH4Cl, then extracted with EtOAc (3×20 mL), the combined organic phases were washed with H2O, brine, and dried over Na2SO4, and filtered, and concentrated to give crude product (S)-tert-butyl 4-((R)-5-hydroxy-2-(tosyloxymethyl)pentyl)-2,2-dimethyloxazolidine-3-carboxylate (255 mg, 92%). It was used without further purification.

1. additionAfter the addition
2. customThe reaction was quenched with MeOH (2 mL)
3. stirringstirred 2 hr
4. extractionThe resulting solution was extracted with DCM (3×20 mL)
5. concentrationthe combined organic phases were concentrated
6. dissolutiondissolved in THF/MeOH (10 mL, 4/1
7. stirringstirred at this temperature for 30 min
8. customThe reaction was quenched by aqueous NH4Cl
9. extractionextracted with EtOAc (3×20 mL)
10. washthe combined organic phases were washed with H2O, brine
11. dry with materialdried over Na2SO4
12. filtrationfiltered
13. concentrationconcentrated

ORDレコード

ord-08727e1eed1c49e4b45696639b551c7e

出典データセット

uspto-grants-2013_11

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08580823B2