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

Participants

Reaction Conditions

Reaction Steps

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.

Provenance & Evidence