Methylvinlketone에 對한 Mercaptans의 添加反應에 관한 速度論的 硏究 = The Kinetics and Mechanism of Nucleophilic Addition Reaction of Mereaptans to Methylvinylketone

다국어 초록 (Multilingual Abstract)

The rate constants for the addition of n-propyl- and n-butylmercaptan to methylvinylketone were determined by iodometry at various pH and temperatures.
From these rate constants, we obtained a rate equation
K??=k??+k'[OH??]=??????????=k'[OH??]
which can be applied over wide pH range. We also calculated the activation parameters(△H??, △S??)
From the values obtained above, we reached the conclusion as follows:
1. The reaction is initiated by addition of n-propyl- and n-butylmercaptan molecule below pH 4.
2. The reaction is proceeded by the n-propyl- and n-butylmercaptied ion above pH 6.
3. At pH 4-6, the complex addition reaction mechanism can also be fully explained by the equation obtained.
4. The mercaptan having longer carbon chain has the smaller nucleophilicity, which is based on the values of calculated activation parameters, and this result is in accord with our expectation.