Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1054444Generated: October 26, 2026

1,2-Dibromoethane → 7-Fluoro-5-nitro-2,3-dihydrobenzo[b][1,4]dioxine

https://huagongshe.com/reaction/1054444

Reaction equation

Participants

RoleNameHCIDCharge
Reactant1,2-DibromoethaneHCID 7839—
ReactantPotassium CarbonateHCID 11430—
Reactant5-Fluoro-3-nitrobenzene-1,2-diolHCID 68816370—
SolventDimethylformamideHCID 6228—
SolventEthyl AcetateHCID 8857—
Product7-Fluoro-5-nitro-2,3-dihydrobenzo[b][1,4]dioxineHCID 6881715099%

Reaction Steps

K2CO3 (15.27 g, 110.6 mmol) was added to a solution of 5-fluoro-3-nitrobenzene-1,2-diol (5 g, 28.9 mmol) in DMF (35 mL) followed by the addition of 1,2-Dibromoethane (13.63 g, 6.25 mL, 72.5 mmol) and stirring was continued at 80° C. for 2 h. Reaction mixture was diluted with ethyl acetate, washed with cold water, dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford the crude, which was purified by MPLC (silica gel, Mobile Phase: ethyl acetate in n-Hexane 0 to 5% as eluant) to afford 7-fluoro-5-nitro-2,3-dihydrobenzo[b][1,4]dioxine (Int-26) (5.7 g, 85% yield) as pale yellow solid. 1H NMR (300 MHz, CDCl3) δ 7.3-7.2 (1H, dd), 6.9-6.8 (1H, dd), 4.4 (4H, s) ppm.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09394305B2
Source datasetuspto-grants-2016_07
ORD IDord-ecd71a84c7fe4fe9aa8a3f60bc7be679
Source noteuspto-grants-2016_07