摘要
本文通过元素分析、磁化率、红外光谱、紫外可见光谱进一步确定了碘化四(4-三甲胺苯基)卟啉铁(Ⅲ)配合物的组成和结构。pH滴定曲线证明它在不同pH水溶液中存在单体和二聚体平衡。通过pH光度法求出在恒定离子强度下(μ=0.1FNaNO_3)聚合物的聚合度、聚合平衡常数及其热力学参数。用分光光度法测定了该二聚体与生物轴向配体(咪唑、1-甲基咪唑、L-组氨酸及吡啶)反应平衡常数及热力学参数,其配位能力大小顺序为:咪唑>1-甲基咪唑>L-组氨酸>吡啶。还求出上述反应在水-二氧六圜混合溶剂中的平衡常数,得lgK与1/ε呈线性关系(ε为介电常数),并对热力学参数进行了讨论。
The composition and structure of tetrakis-(p-trimethyl-ammoniumphenyl)
porphyrinatoiron (Ⅲ) iodide, [Fe(Ⅲ)TAPPI], have been established by elemental
analysis, magnetic susceptibility measurement, IR and UV spectra. The pH titration
curves indicated that there is an equilibrium between monomer and dimer of Fe (Ⅲ)
TAPPI in the aqueous solution at different pH values. The polymerization numbers (n)
and dimerization equilibrium constants (K_D) at constant ionic strength and the
thermodynamic parameter of polymerization reaction have been obtained from spectro-
photometric pH titration curves. The equilibrium constants of reaction between Fe(Ⅲ)
TAPPI dimer and different axial ligands (imidazole, 1-methylimidazole, L-histidine and
pyridine) and their thermodynamic parameters in water and water-dioxane mixed
solvent have been determined by spectrophotometry. The thermodynamic parameters
have been discussed.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
1989年第2期128-132,共5页
Acta Chimica Sinica
