谷氨酸和精氨酸与铜离子混配合物的热化学

Thermochemical Study of Mixed-ligands Complexes of L-glutamic Acid and L-arginine Acid with Copper lons

合成了谷氨酸和精氨酸与铜（Ⅱ）离子混配型配合物．经化学分析和元素分析及热重分析确定了配合物的组成，并采用溶解量热法在自行研制的具有恒定温度环境反应热量计上分别测定了反应物 Ｌ－Ｇｌｕ（ｓ）＋Ｌ－Ａｒｇ（ｓ）］、ＣｕＳＯ４·５Ｈ２Ｏ（ｓ）和产物Ｃｕ·Ｇｌｕ·Ａｒｇ·ＳＯ４·５Ｈ２Ｏ（ｓ）溶解在２ ｍｏｌ·Ｌ－１Ｈ２ＳＯ４溶液中的溶解焓．通过所设计的热化学循环求出配位反应的焓变△ｒＨｍ，进而计算出混配型配合物的标准生成烙，其值为△ｒＨｍ（Ｃｕ·Ｇｌｕ·Ａｒｇ·ＳＯ４·５Ｈ２Ｏ）＝－３ ９２３．１４５ ｋＪ·ｍｏｌ－１．

The Mixed-ligands complexes of L-glutamic acid and L-arginine with Cu(Ⅱ) was synthesized. The composition of the complex was determined by chemical analysis, element analysis and thermal gravity analysis. By solution calorimetry in a reaction calorimeter at 298. 2 K, the dissolution enthalpy for the reactant, CuSO4 5H2O(s ), L-Glutamic acid(s ) and L-Arginine (s ), and the product, Cu·Glu·Arg·SO4·5H2O(s ), were deter- mined. They were dissolved in 2 mol·L-1 H2SO4 solution, respectively. A themochemistry cycle was designed, to obtain the coordinate reaction enthalpy change, △Hm = (19. 745 ±0. 033) kJ·mol -1, and the standard forma- tion enthalpy of the mixed-ligands complex was calculated, △fHm,Cu· Glu·Arg·SO4·5H2O(s) = (- 3923. 145 ±3. 768 ) kJ· mol - 1. This result offers a basic thermochemistry parameter for the further research of this kind of compounds.