Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1408432Generated: November 4, 2026

Ethylene Glycol → 6-Bromospiro[2H-1-benzopyran-3(4H),2'-[1,3]dioxolane]

https://huagongshe.com/reaction/1408432

Reaction equation

Participants

RoleNameHCIDCharge
ReactantEthylene GlycolHCID 174—
Reactantp-Toluenesulfonic acidHCID 6101—
Reactant6-bromo-3,4-dihydro-2H-1-benzopyran-3-oneHCID 58466622—
SolventTolueneHCID 1140—
Product6-Bromospiro[2H-1-benzopyran-3(4H),2'-[1,3]dioxolane]HCID 6715122494.7%

Reaction Conditions

Temperature100 °C

Reaction Steps

To a solution of 6-bromo-2H-1-benzopyran-3(4H)-one (300 mg, 1.13 mmol) in toluene (2 mL) was added ethyleneglycol (163 mg 2.64 mmol) and para-toluenesulfonic acid (27 mg, 0.13 mmol). The reaction mixture was heated at 100° C. for 6 hrs. The reaction mixture was cooled and the solvent concentrated. The resultant residue was partitioned between ethyl acetate and water. The organic phase was washed with water, brine, dried over Na2SO4 and concentrated under vacuum to give the title compound (290 mg, 79% yield) as a solid.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS08921360B2
Source datasetuspto-grants-2014_12
ORD IDord-c80036f10e2745eda52e07e53243a9f5
Source noteuspto-grants-2014_12