• 제목/요약/키워드: Kinetic isotope

검색결과 145건 처리시간 0.019초

Nucleophilic Substitution Reactions of 2-Chloro-2-Propen-1-yl Arenesulfonates with Anilines and N,N-Dimethylanilines in Acetonitrile

  • 오혁근;정은미;이익춘
    • Bulletin of the Korean Chemical Society
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    • 제19권12호
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    • pp.1334-1336
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    • 1998
  • Kinetic studies are carried out on the reactions of 2-chloro-2-propen-1-yl arenesulfonates with anilines and N,N-dimethylanilines in acetonitrilile at 45.0 ℃. The 2-chloro substituent is found to deactive the allyl moiety with considerable decrease in the rates. The sign and magnitude of the cross-interaction constant (ρxz 0.3) and the inverse secondary kinetic isotope effect (kH/kD 0.92) support an SN2 mechanism with a relatively tight transition state. The possibility of an SN2' mechanism can be safely precluded based on the ρxz values observed.

Kinetics and Mechanism of the Reactions of S-Phenyl Dithiobenzoates with Benzylamines in Acetonitrile

  • 오혁근;신철호;이익춘
    • Bulletin of the Korean Chemical Society
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    • 제16권7호
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    • pp.657-661
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    • 1995
  • Kinetic studies are carried out on the reaction of S-phenyl dithiobenzoates with benzylamines in acetonitrile at 30.0 ℃. Small magnitude of ρX (βX) as well as ρZ (βZ) obtained suggests rate-limiting nucleophilic attack of the thiocarbonyl carbon. This is supported by the unusually small magnitude of ρXY and ρYZ, albeit their signs do not agree with those expected. Moreover, the inverse secondary kinetic isotope effects (kH/kD<1.0) involving deuterated benzylamine nucleophiles are also in line with the proposed mechanism.