Diisobutylaluminum hydride → HCID 131736323, compound

Participants

Reaction Conditions

Reaction Steps

tert-Butyl 7-fluoro-3-oxo-2,3-dihydro-4H-1,4-benzoxazine-4-carboxylate (Intermediate 6, 2.22 g, 8.31 mmol) was dissolved in THF (20 mL) and cooled to −78° C. DIBAL-H (1 M in toluene, 10.8 mL, 10.8 mmol) was added at a rate to maintain the reaction temperature at below −70° C., and the reaction was thereafter stirred at −78° C. for 50 min. The cooling was removed and the reaction was quenched with NH4Cl (aq. sat. 10 mL). The mixture was allowed to reach rt. The reaction mixture was diluted with DCM and Rochelle's salt (30% aq., 100 mL) and extracted with DCM (2×100 mL). The organics were combined, washed with brine, dried over magnesium sulphate, filtered through a phase separator and concentrated to give the title compound (2.23 g, 100%) as a white solid.

Provenance & Evidence