Spectroscopic elucidation of the interaction of native cyclodextrins and their acetylated derivatives with asymmetric monomethyne cyanine dye

Five novel complexes of asymmetric monomethyne cyanine dye (1), with α-, β-, γ-cyclodextrins and the corresponding functionalized derivatives, namely acetyl-β-(Ac-β-CD) and acetyl-γ-(Ac-γ-CD) cyclodextrins were studied by means of UV–VIS, linear-polarized infrared and fluorescence spectroscopy, as well as scanning electron microscopy, powder X-ray diffraction, and thermal methods both in solution and in solid-state. Computational chemistry methods were employed with the purpose of elucidating the electronic structure and vibrational properties of the organic dye.