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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 270769Generated: October 30, 2026

Ethanol → Ethyl 4-(piperazin-1-yl)benzoate

https://huagongshe.com/reaction/270769

Reaction equation

Participants

RoleNameHCIDCharge
ReactantEthanolHCID 702—
ReactantSulfuric AcidHCID 1118—
ReactantPiperazineHCID 4837—
ReactantPotassium IodideHCID 4875—
ReactantPotassium CarbonateHCID 11430—
Reactant4-Bromobenzoic acidHCID 11464—
CatalystTetrabutylammonium IodideHCID 67553—
SolventDimethylformamideHCID 6228—
ProductEthyl 4-(piperazin-1-yl)benzoateHCID 2761178—

Reaction Conditions

Temperature85 °C

Reaction Steps

To 4-bromobenzoic acid (25 g) and ethanol (1000 mL) was added conc.sulfuric acid (20 g) drop wise. The reaction mixture was heated at 85° C. overnight. The reaction was cooled and ethanol was removed by distillation and the reaction mixture quenched with water and extracted with ethyl acetate. The extract was washed with 10% sodium bicarbonate, water, brine and then concentrated to yield the crude ester. 4-bromoethyl benzoate (10.0 g, 0.0437 mol) was taken into 250 mL of dry DMF, piperazine (37 g, 0.437 mol) was added, followed by 30 g (0.2185 mol) of dry potassium carbonate, 1.0 g of TBAI and 1.5 g of potassium iodide. The reaction mixture was heated at 135° C. for over night. The reaction mixture was quenched with water and extracted with ethyl acetate. The extracts were washed with water, then brine and then concentrated to yield 4-Piperazin-1-yl-benzoic acid ethyl ester as an off-white solid.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS07449576B1
Source datasetuspto-grants-2008_11
ORD IDord-508e216829a24e26862ec96a9f1cbe0d
Source noteuspto-grants-2008_11