Thermodynamics of Macrocycle Complexation Chemistry.Interactions of Metal Ions with Double-Armed N-Pivot Lariat Ethers in Methanol and Methanol-Water Solutions at 25.0 .degree.C
Thermodynamics of Macrocycle Complexation Chemistry.Interactions of Metal Ions with Double-Armed N-Pivot Lariat Ethers in Methanol and Methanol-Water Solutions at 25.0 .degree.C
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大环络合化学的热力学。25.0℃下金属离子与双臂N-枢轴套索醚在甲醇和甲醇-水溶液中的相互作用
DOI：
10.1021/ic00084a006
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发表时间：
1994
影响因子：
4.6
通讯作者：
J. Bradshaw
中科院分区：
文献类型：
--
作者：
R. Izatt;Xianxin Zhang;Haoyun An;C. Zhu;J. Bradshaw
本文用量热滴定法测定了Na +、K +、Cu 2+和Ca 2+与一系列N，N ′-二枢轴醚在9：1（v/v）CH 3OH/H2O和无水甲醇中相互作用的log K、ΔH和TΔS值。通过在母体大环上引入含氧或氮原子的侧臂，大大提高了配合物的稳定性。焓变和熵变支持侧臂与阳离子相互作用的观点。Ca 2+络合物的形成是焓和熵稳定的。所有其他的相互作用都是焓驱动的，熵变是不利的
The log K, ΔH, and TΔS values for interactions of Na + , K + , Cu 2+ , and Ca 2+ with a series of N,N'-dipivot lariat ethers have been determined from calorimetric titration data valid in 9:1 (v/v) CH 3 OH/H 2 O and absolute methanol at 25.0 o C. Complex stability is increased greatly by introducing pendant arms containing oxygen or nitrogen atoms to the parent macrocycles. The enthalpy and entropy changes support the idea that the side arms interact with the cations. Formation of complexes of Ca 2+ is both enthalpy and entropy stabilized. All other interactions are enthalpy driven, and the entropy changes are unfavorable