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Journal of the Korean Chemical Society (JKCS)

ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 26, Number 6
JKCSEZ 26(6)
December 20, 1982 

 
Title
Kinetic Studies on the Nucleophilic Addition of Cysteine to 3,4-Methylenedioxyphenylmethylene Malononitrile

3,4-Methylenedioxyphenylmethylene Malononitrile에 대한 Cysteine의 친핵성 첨가반응에 관한 반응속도론적 연구
Author
Tae-Rin Kim, Dong-Suk Rho, Young-Haeng Lee

김태린, 노동석, 이영행
Keywords
Abstract
3,4-methylenedioxyphenylmethylene malononitrile에 대한 cysteine의 친핵성 첨가반응 속도를 측정하여 염기성 및 산성용액에서의 반응메카니즘을 제안하였고 넓은 pH범위에서 잘 맞는 반응속도식을 구했다. 이 반응속도식으로 부터, pH 9.0 이상에서는 hydroxide ion 농도에만 비례하고, pH 6.0 이하에서는 cysteine의 중성분자만이 첨가하며, pH 7~9.0에서는 cysteine 중성분자와 그의 음이온이 경쟁적으로 첨가됨을 알 수 있었고 첨가되는 cysteine 중성분자와 음이온의 비도 계산할 수 있었다.

The rate constants of the nucleophilic addition of cysteine to 3,4-methylenedioxyphenylmethylene malononitrile were determined by UV Spectrophotometry and a rate equation which can be applied over wide pH range was obtained. On the basis of rate equation, it may be concluded that the rate constants were dependent upon only the concentration of hydroxide ion above pH 9.0, however, below pH 6.0, the reaction were initiated by the addition of neutral cysteine molecule to carbon-carbon double bond and at pH 7.0~9.0, the addition of a neutral cysteine molecule and it's anion occurred competitively.

Page
407 - 413
Full Text
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