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Journal of the Korean Chemical Society (JKCS)

ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 19, Number 1
JKCSEZ 19(1)
February 20, 1975 

Nucleophilic Substitution at a Carbonyl Carbon Atom (V). Kinetic Studies on Halogen Exchange Reactions of N,N-Dialkylcarbamoyl Chlorides in Dry Acetone

카르보닐 탄소원자의 친핵치환 반응 (제5보). 아세톤 용매속에서의 Dialkylcarbamoyl Chloride의 할로겐 교환반응에 관한 속도론적 연구
Shi Choon Kim, Ikchoon Lee

김시준, 이익춘
Carbonyl 탄소원자의 반응성에 대한 연구의 일환으로 N,N-imehtylcarbamoyl chloride와 N,N-diethylcarbamoyl chloride의 할로겐 교환반응을 아세톤 용매속에서 방사성 할라이드 이온을 사용하여 두 온도에서 속도론적으로 연구하였다. 그 결과를 alkylchloroformate의 경우와 비교하면, 친핵성의 순서는 비슷한 경향을 나타내나, 반응속도는 가용매분해나 alkylchloroformate의 경우보다 느리다. 활성화 피라미터 ΔH나 ΔS는 Cl->Br->I-순서로 감소한다. 이 결과를 용매화 효과, bond-breaking, bond-formation 및 electronic requirment로 설명하였다.

Kinetic study of halogen exchange for N,N-dimethylcarbamoyl chloride and N,N-diethylcarbamoyl chloride in acetone by using radioisotopic halide ions has been carried out at two temperatures as a part of studying the reactivity of carbonyl carbon atom. The order of nucleophilicity showed a similar tendency as that for alkyl chloroformate, but reaction rate is much slower than that for solvolysis and alkyl chloroformate. The activation parameters, ΔH≠ and ΔS≠ were found to decrease in sequence Cl- > Br- > I- for N,N-dialkylcarbamoyl chlorides. The results are interpreted in terms of solvation effect, degree of bond-breaking and bond-formation and electronic requirements.

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