Spectroscopic Study of Bifenox Complexation with α-, β- and γ-Cyclodextrin in Solution and Solid State

Aims: To study the host-guest interactions of α-, β- and g-cyclodextrin with herbicide bifenox.

Study Design: Binding constants of the complexes were determined by Benesi-Hildebrand method and stoichiometry of the complexes was confirmed by Job’s method. In addition, by means of FT-IR and 1H-NMR spectral analysis, the host-guest interaction of inclusion complexes was deduced.

Place and Duration of Study: Research Department of Chemistry, Aditanar College of Arts and Science, Tiruchendur, Tamil Nadu, India. July 2013-November 2013.

Methodology: Absorption spectrum was recorded with a Systronics-2201 UV-visible spectrometry. FT-IR spectra were obtained with Shimadzu FT-IR spectrometer using KBr pellet. 1H-NMR spectra were recorded with Bruker 300 MHz spectrometer.

Results: The observed results of this study indicate the favoured modes of inclusion of bifenox inside the cavity of cyclodextrins. The experimental results show that the mode of inclusion is the benzene ring with-C-Cl part of the bifenox molecule into the cyclodextrin cavity.

Conclusion: UV-visible, FT-IR and 1H-NMR studies proved the formation of inclusion complex between cyclodextrins and bifenox in solution and solid state.