荧光法测定冠醚络合物稳定常数的研究

THE DETERMINATION OF THE STABILITY CONSTANTS OF METAL-CROWN ETHER COMPLEXES BY FLUORIMETRIC METHOD

1967年C.J.Pedersen发表了关于冠醚(环聚醚)及其金属络合物的研究以来,冠醚对金属离子的特殊络合作用引起了人们极大的兴趣。碱金属冠醚络合物的发现不仅对络合物本身是个新的发展,而且在有机合成化学、分析化学及生物化学等领域中都引起了很大的反响.

The stability constaut of Tl^(+) complex of 18-crown-6 iu methauol solution was determined by the fluorescent quenching of Tl^(+).Those of Na^(+),K^(+) and La^(3+) complexes were determined by competitive coordination.The values of logK for Na^(+) and K^(+) measured by this method were found in excellent agreement with those determined potentiometrically using ion selective electrodes.The value of logK for La^(3+) was found to be higher than that determined calorimetricallg by Izatt.It is proposed that this discrepancy may be caused by the difference of water content in methanol.