Structure and Reactivity of α,β-Unsaturated Ethers. X. The Acid-Catalyzed Hydrolysis of Ring-Substituted Styryl Ethyl Ethers
1970; Oxford University Press; Volume: 43; Issue: 10 Linguagem: Inglês
10.1246/bcsj.43.3256
ISSN1348-0634
AutoresTadashi Okuyama, Takayuki Fueno, Junji Furukawa,
Tópico(s)Molecular spectroscopy and chirality
ResumoThe acid-catalyzed hydrolysis of cis- and trans-styvyl ethyl ethers (SEE) and several of their ring-substituted derivatives has been kinetically investigated in 80% aqueous dioxane. It has been found that these ethers are less reactive than vinyl ethyl ether by a factor of ca. 500 and that all the cis isomers studied are about twice as reactive as the corresponding trans isomers. The hydrolysis of the substituted ethers at 35°C has proved to obey the Hammett relation with the reaction constants ρ=−1.07 and −0.70 for the cis and the trans isomers, respectively. All these results appear to be interpretable at least qualitatively in terms of the reaction scheme involving the rate-determining protonation to the β-carbon atom.
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