Abstract
Multidentate N,O-containing ligands, such as N,N'-bis(2-hydroxybenzyl)-ethylenediamine(BHED), N,N'-bis(2-hydroxybenzyl)-propylenediamine(BHPD), N,N'-bis(2-hydroxybenzyl)-diethylenetriamine(BHDT), N,N'-bis(2-hydroxybenzyl)-triethylenetriamine(BHTT) and N,N'-bis(2-hydroxybenzyl)-tetraethylenepentaamine (BHTP) were synthesized by reduction of the imine group of Bis(salicylidene)-ethylendiamine(BSED), Bis (salicylidene)-propylenediamine(BSPD), Bis(salicylidene)-diethylentriamine(BSDT), Bis(salicylidene)-triethylenetetraamine(BSTT) and Bis(salicylidene)-tetraethylenepentaamine(BSTP). Proton dissociation constants of the ligands and stability constants of transition metal(Ⅱ) ion complexes with BHED, BHPD, BHDT, BHTT, and BHTP were determined by potentiometic titration. The sequence of stability constants $(logK_{ML})$ of complex increases as BHED Zn(Ⅱ) which follows the Irving-Williams series.
여러자리 산소-질소계 리간드들은 시프염기 리간드인 Bis(salicylidene)-ethylendiamine(BSED), Bis(salicylidene)-propylenediamine(BSPD), Bis(salicylidene)-diethylenetriamine(BSDT), Bis(salicylidene)-triethylenetetraamine(BSTT) 및 Bis(salicylidene)-tetraethylenepentaamine(BSTP)의 이민기를 수소환원장치에서 백금촉매를 이용하여 네자리 리간드인 N,N'-bis(2-hydroxybenzyl)-ethylenediamine(BHED)과 N,N'-bis(2-hydroxybenzyl)-propylenediamine(BHPD), 다섯자리 N,N'-bis(2-hydroxybenzyl)-diethylenetriamine(BHDT), 여섯자리 N,N'-bis(2-hydroxybenzyl)-triethylenetriamine(BHTT), 일곱자리 N,N'-bis(2-hydroxybenzyl)-tetraethylenepentaamine(BHTP) 리간드들을 합성하였다. 리간드들의 양성자 해리상수와 전이금속(Ⅱ)과 착물의 안정도상수는 전위차 적정법으로 측정하였다. 리간드별 전이금속(Ⅱ)이온에 대한 착물 안정도상수값$(logK_{ML})$의 크기는 BHED아연(Ⅱ)의 순서로 이 결과는 Irving-Williams 서열과 잘 일치하여 증가하였다.