Synthesis and spectrophotometric study of 4-(6-bromobenzothiazolylazo)‎ orcinol as an analytical reagent for determination of copper

الملخص EN

The new azo reagent 4-[ (6-Bromo-2-benzothiazolyl ) azo] orcinol (6-BrBTAO) was prepared by coupling reaction between (6-bromo-2-benzothiazolyl diazonium ) chloride with orcinol in alkaline solution.

The reagent was examined by using elemental analysis, UV-Vis, and infrared spectra.

A sensitive and selective spectrophotometric method is proposed for the rapid determination of copper (II) using (6-BrBTAO), as anew spectrophotometeric reagent.

The reaction between this reagent and copper (II) is instantaneous at 497 nm (λmax) and pH=4 to form red complex having a mole ratio 1 : 2 (metal : ligand) and the absorbance remains stable for over 24 hr.

Beer's law is obeyed in the range of (5-30) μg.ml-1 with molar absorptivity (Є) = 149×103 L.mol-1.cm-1and a detection limit of 0.355μg.ml-1 The precision and accuracy were obtained to be R.S.D%=0.59%,Re%=99.94% and Erel%= -0.006%.The method is successfully employed for the determination of copper(II) in Amalgum dental filling Sampels .The most important interference were due to Ni2+, Zn2+, Co2+, Cd2+, Pb2+, Ag1+, and Cr3+ and suitable masking agents were used.