The effects of the acyl chain length of activated substrates on the rate of hydrolysis of neutral substrates(Sn) and anionic substrates (Sn^-) catalyzed by imidazole (Im), poly[4(5)-vinylimidazole](PVIm), and the copolymer of 4(5)-vinylimidazole (95.5mole%) and dodecyl methacrylate (4.5mole%) (CPVIlm) were investigated. They indicate the importance of hydrophobic interactions in the rate enhancements observed for CPVIm catalyzed reactions as compared to PVIm and Im catalyzed reactions. In case of neutral esters used as substrates, saturation kinetics were not observed with poly[4(5)-vinylimidazole] as a catalyst, but that was observed with the copolymer that has hydrophobic moiety. In case of anionic esters used as substrates, saturation kinetics were observed with both poly[4(5)-vinylimidazole] and CPVIm. The observation of Michaelis-Menten kinetics in these systems is indicative of the formation of a catalyst-substrate complex as in the case of enzyme systems.

이미다졸(Im), poly[4(5)-vinylimidazole](PVIm), 4(5)-vinylimidazole (95.5mole%)과 dodecyl methacrylate (4.5mole%)의 공중합체 (CPVIm)를 촉매로 하여 활성화된 에스테르의 분해반응을 실시하였다. 기질로는 중성 그리고 음이온성이 선택되었으며 기질의 acyl 구릅의 길이도 변화시켜 보았다. 소수성 상호작용에 의해 CPVIm을 촉매로 하였을 때가 Im이나 PVIm을 촉매로 하였을 때보다도 반응속도 상수값이 컸다. 중성기질을 사용하였을 때, PVlm을 촉매로 하였을 경우는 saturation kinetics가 나타나지 않았지만 보다 더 소수성인 CPVIm을 촉매로 하였을 경우는 saturation kinetics가 나타났다. 음이온성기질을 사용하였을 때는 PVIm, CPVIm 모두 saturation kinetics를 나타냈다. 이 실험에서 Michaelis-Menten kinetics의 관측은 효소작용에서와 같이 촉매-기질 복합체가 형성됐음을 나타낸다.

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