Hydrogen Peroxide → HCID 118599754, compound

Participants

Reaction Conditions

Reaction Steps

A 1 M solution of lithium triethylhydroborate (13.75 mL, 13.75 mmol) in THF was added dropwise to a solution of tert-butyl 7-chloro-3-oxo-2,3-dihydro-4H-1,4-benzoxazine-4-carboxylate (Intermediate 16, 3.25 g, 11.5 mmol) in anhydrous THF (60 mL) at −78° C. under N2 (g). After stirring at −78° C. for 45 min, the mixture was treated with Na2CO3 (sat. aq., 25 mL); then H2O2 (35% in aq, 25 mL) was slowly added at −15° C. The mixture was stirred at rt over night, then filtered. The filtrate was concentrated in vacuo and the residue was extracted with EtOAc (2×100 mL). The organic phase was washed with brine (100 mL), dried by passage through a phase separator, and concentrated under reduced pressure giving the title compound (3.29 g, 101%) as an off-white solid that was used without further purification.

Provenance & Evidence