6-Nitro-2H-1,4-benzoxazin-3(4H)-one → 6-nitro-3,4-dihydro-2H-1,4-benzoxazine

A solution of BH3-Me2S in THF (2 M, 7.75 mL, 15.5 mmol) was added dropwise to a suspension of 6-nitro-4H-benzo[1,4]oxazin-3-one (0.6 g, 3.1 mmol) in THF (10 mL). The mixture was stirred at room temperature overnight. The reaction was quenched with MeOH (5 mL) at 0° C. and then water (20 mL) was added. The mixture was extracted with Et2O and the combined organic layers were washed with brine, dried over Na2SO4 and concentrated to give 6-nitro-3,4-dihydro-2H-benzo[1,4]oxazine as a red solid (0.5 g, 89%), which was used without further purification.

1. customThe reaction was quenched with MeOH (5 mL) at 0° C.
2. additionwater (20 mL) was added
3. extractionThe mixture was extracted with Et2O
4. washthe combined organic layers were washed with brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated

ORD record

ord-266f0cc563c9460f8dbee07c1ca3fab1

Source dataset

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08629162B2