Diisobutylaluminum hydride → HCID 90373394, compound

Participants

Reaction Conditions

Reaction Steps

To a 500 mL 3-neck round-bottomed flask equipped with internal temperature monitoring and a magnetic stir bar was added (5)-tert-butyl 3-(6-bromo-3-fluoropyridin-2-yl)-3-((R)-1,1-dimethylethylsulfinamido)-4-fluorobutanoate (8.90 g, 19.55 mmol) and DCM (200 mL). The solution was cooled to −78° C. and DIBAL-H (Aldrich; 48.9 mL, 48.9 mmol, 1.0 M in hexane) was added over 30 min with the solution running down the side of the flask to precool it. The solution did not go above −74° C. during the addition. After 75 min at −78° C., an additional 5 mL of the DIBALH solution was added. After 10 min the solution was quenched with MeOH (4 mL) dropwise with the MeOH running down the inside of the flask. The solution was allowed to warm to rt and 4 mL of sat NaHCO3 was added. This was stirred for 10 min and then solid Na2SO4 was added (˜20 g). This was stirred for 10 min and then filtered through Celite and the filtercake was washed with DCM. The filtrate was concentrated onto silica. Purification by silica gel chromatography (Gradient: 0.0 to 60% EtOAc/hexane) afforded (R)-N-((S)-2-(6-bromo-3-fluoropyridin-2-yl)-1-fluoro-4-oxobutan-2-yl)-2-methylpropane-2-sulfinamide (5.08 g, 13.25 mmol, 67.8% yield) as a pale yellow oil. MS m/z=383.0 [M+H]+. Calculated for C13H17BrF2N2O2S: 382.0.

Provenance & Evidence