Synthesis of New Tetra Triazole Functionalized Calix[4]resorcinarene and Chemosensing of Copper Ions in Aqueous Medium

A new tetra triazole functionalized calix[4]resorcinarene macrocycle (5) is synthesized and utilized for the detection of copper ions in the aqueous medium. The photophysical potential of compound (5) is examined by a range of cations (Ba2+, Ca2+, Co2+, Hg2+, K+, Mg2+, Mn2+, Na+, NH4 + and Pd2+). The triazole based calix[4]resorcinarene macrocycle (5) has interacted with Cu2+ ion in preference of other cations. A significant quenching has been observed after the addition of 15 μM Cu2+ ion solution, which produced 4.2 folds drift in the absorption intensity of compound (5). Tetra triazole functionalized calix[4]resorcinarene macrocycle showed high selectivity towards copper ion chemosensing without any interference in competitive studies. The pH studies of compound (5) with Cu2+ indicated the maximum chelation between 7- 7.5 pH. The compound (5) is capable to recognize Cu2+ at 1 μM detectable limit. Copper ion was detected in tap water with 15 μM concentration. Job’s plot showed 1:2 binding ratio between macrocycle (5) and Cu2+.

Recognition of Cyanide by Urea-Based Bipodal Probe

Two urea based colorimetric receptors were developed. The receptor L showed a exclusive selectivity of cyanide over the other anions in acetonitrile solution and exhibited Intramolecular charge Transfer (ICT). It was studied by UV-vis spectroscopy and their binding ability was explored by using Job’s plot and Benesi-Hildbrand routes. From that the receptor L, it recognize CNanions and it indicates 1:1 stoichiometric ratio and the receptor L 1 (monofluoro substituted) does not recognize any anions. Finally the (difluoro substituted) receptor L shows good sensitivity, selectivity towards cyanide.