Abstract
The formation of inclusion complexes between ${\beta}$-cyclodextrin and diethylenetriamine substituted-pyridine copper(II) perchlorate; [Cu(dien)(sub-py)] $(ClO_4)_2$, were studied by spectrophotometric methods. On account of charge-transfer band(MLCT) and $^2T_2{\rightarrow}^2E$, the two high peaks were observed as an inclusion complex for the [${\beta}$-CD]$[Cu(dien)(p-Cl-py)]^{2+}$ in the ultraviolet region of the spectrum. The ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion formed a 1:1 complex, and the formation constants were decreased with the increasing temperatures, due to weak binding energy between ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion. This reaction was controlled by enthalpy. In a correlation of the Hammett substituent constants and formation constants for the reaction, formation constants were increased by strong binding energy in the inclusion complexes when electron donating groups were substituted in pyridine ring.
분광 광도법을 이용하여 ${\beta}$-CD와 $[Cu(dien)(sub-py)]^{2+}$ 이온 간의 복합체 형성에 관한 연구를 하였다. ${\beta}$-CD와 $Cu^{2+}$ 착물이 복합체를 형성 할 때 ${\gamma}_{max}$은 리간드에 전자 주는기($CH_3$)가 치환 된 경우는 $^2T_2{\rightarrow}^2E$로 한 곳에서, 전자 끄는기(Cl)가 치환된 경우는 $^2T_2{\rightarrow}^2E$와 MLCT에 의하여 두 곳에서 나타났다. 형성상수는 온도가 올라가면 결합에너지의 감소로 작아졌다. 모든 반응은 엔트로피의 감소를 보였으나 큰 발열반응으로 자발적 반응이었다. 치환기 상수(${\sigma}_x$)에 따른 Hammett plot 결과 좋은 직선성(${\gamma}=0.996$)을 보여 형성상수를 정량적으로 설명할 수 있었다.
