Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 2102948Generated: October 25, 2026

Hydrochloric Acid → 3,4-Dihydro-2H-1,4-benzoxazin-6-amine

https://huagongshe.com/reaction/2102948

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantTetrahydrofuranHCID 8028—
ReactantSodium HydroxideHCID 14798—
Reactant6-amino-3,4-dihydro-2H-1,4-benzoxazin-3-oneHCID 2763681—
SolventEthanolHCID 702—
SolventWaterHCID 962—
Product3,4-Dihydro-2H-1,4-benzoxazin-6-amineHCID 1134410251%

Reaction Conditions

Temperature80 °C

Reaction Steps

6-Amino-2H-benzo[b][1,4]oxazin-3(4H)-one (590 mg, 3.6 mmol) was added to a THF solution of borane tetrahydrofuran complex (9 mL, 1M solution) and the reaction mixture was refluxed for 2.5 h. EtOH (2 mL) was added and stirred at 70° C. for 1 h before 1 mL HCl (conc.) was added. The mixture was stirred at 80° C. overnight then the volatiles were removed under vacuum to leave a crude reside. The residue was dissolved in water, NaOH was added until pH˜10, and the mixture was extracted with CH2Cl2. The organic phase was washed with water and the solvent was removed under vacuum. The residue was purified by column chromatography on silica gel to give the product (274 mg, 51%) as a colorless oil.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS07576099B2
Source datasetuspto-grants-2009_08
ORD IDord-c67f3e46d0fb4a3fb1d7089e312c0f84
Source noteuspto-grants-2009_08