The influence of the acid type and amount used for peptization of aluminum hydroxide on crystallinity of the boehmite as well as the pH of sols was investigated. X-ray diffractograms of boehmite powders showed decrease in crystallinity at higher ratio of acid to aluminum hydroxide and depends on the pH of sols. The boehmite was calcinated at 350 and 600°C to yield ?-Al 2 O 3 catalysts. These catalysts then characterized by N 2 absorption (BET), Xray diffraction (XRD), scanning electron microscopy (SEM) and infrared spectroscopy (IR). In order to test the reactivity and selectivity of calcined catalysts, dehydration reaction of a secondary alcohol (2-octanol) was carried out over these catalyst. There was a good correlation between product distribution and catalyst acidity. Catalyst prepared under stronger acidic condition resulted isomeriztion of 1-octenes and 2-octenes to 3-octenes. In this study conformational analysis and anomeric effect of 2-substituted-1,4- dioxanes (X = NO 2 , CN, F, Cl, Br, Me, Et, t-Bu, OH, OMe , NH 2 ) are calculated and compare to the values of the similar substituted cyclohexanes. The energy differences between the axial and equatorial conformers, endo and exo-anomeric effect, repulsive non-bond and H-bonding interactions are investigated. Ab initio HF/6-31G*, MP2/6-31G* and DFT/B3LYP/6-31G* methods were used to calculate the bond lengths, bond angles, torsion angles, relative energies and conformational analysis of axial and equatorial conformers of 2-substituted 1,4- dioxanes.
