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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1448622Generated: October 25, 2026

Water → 2-(2-Hydroxyethyl)cyclopent-2-en-1-one

https://huagongshe.com/reaction/1448622

Reaction equation

Participants

RoleNameHCIDCharge
ReactantWaterHCID 962—
ReactantBoron tribromideHCID 25134—
ReactantHCID 13289786HCID 13289786—
SolventDichloromethaneHCID 6344—
Product2-(2-Hydroxyethyl)cyclopent-2-en-1-oneHCID 15414494—

Reaction Steps

The enol acetate of Example 10 is brominated and dehydrobrominated by the method described in Example 28 of Belgium Pat. No. 786,215. The crude product is then dissolved in methylene chloride and is added at -78° C. to a methylene chloride solution containing about seven molar equivalents of boron tribromide. After one hour at -78° C. the solution is allowed to warm to room temperature and is then kept at ambient temperatures for a total of eighteen hours. The mixture is poured into water and extracted with ether. The organic phase is washed with saturated saline solution, then water and is dried. Evaporation of solvents leaves subject product, which is purified by distillation. The combined organic phases are washed with ice cold 5% sodium hydroxide solution, ice cold 5% hydrochloric acid, and saturated sodium chloride solution, dried with anhydrous magnesium sulfate and taken to dryness. Distillation gives a pale yellow oil; λ max 5.85μ (carbonyl group).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS04180677
Source datasetuspto-grants-1979_12
ORD IDord-b8b76181fab5481f9d71157620052625
Source noteuspto-grants-1979_12