Hydrochloric Acid → 7-(hydroxymethyl)-2,2-dimethyl-2H-1,4-benzoxazin-3(4H)-one

Participants

Reaction Steps

To a solution of methyl 2,2-dimethyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-7-carboxylate (1.00 g) in tetrahydrofuran (50 mL) was added dropwise 1M diisobutyl aluminum hydride solution in toluene (13.1 mL) under cooling in dry ice/acetone bath under argon atmosphere, and the mixture was stirred at the same temperature for 2.5 hours. Thereto was further added 1M diisobutyl aluminum hydride solution in toluene (8.5 mL), and the mixture was stirred at the same temperature for 1.5 hours. The reaction mixture was poured to an aqueous 2N HCl solution, and the mixture was extracted with diethylether. The organic layer was washed successively with an aqueous saturated sodium hydrogencarbonate solution and brine, dried over sodium sulfate and concentrated in vacuo. The residue was triturated in ethyl acetate to give 7-(hydroxymethyl)-2,2-dimethyl-2H-1,4-benzoxazin-3(4H)-one (389 mg) as a colorless powder.

Provenance & Evidence