New, rapid and accurate spectrophotometric procedure was developed, to determine the 6-(trifluoro methyl)furo[2, 3-b]pyridine-2-carbohydrazide analogues in pure form. The method was based on the reaction of these analogues as n-electron donors with the sigma-acceptor iodine. The obtained charge transfer complexes were measured at 370 nm for iodine in water. The obtained complexes were examined by using the UV, IR and 1H NMR spectral analysis. A complete detailed investigation of the formed complex was made with respect to the association constant and free energy change. The association constants were calculated using iodine method and Rose-Dragoequation. The values of association constants show a strong donor-acceptor interactions, which help to study the possible site of interaction between the donors and the acceptors.
Spectrophotometry, Charge transfer complexes, Fluoro-pyrine-2-carbohydrazides, Iodine