NaNp/CpTiCl3/Al2O3-SiO2 (Cp = cyclopentadienyl; Np = napthenide anion) systems are new catalysts active in the C=C hexene-1 bond isomerization reaction. Their activity depends on amount of titanium[III] hydride surface complexes and the support Lewis acidity. As results showed, all these properties are a function of the Al2O3-SiO2 gels composition. The highest yields were obtained for the 90 and 100 wt.% Al2O3 catalysts (Lewis acidity) and for the 10 and 60 wt.% Al2O3 catalysts (amount of Ti[III] + Lewis acidity). (C) 2012 Elsevier Inc. All rights reserved.