Functionnalization of mesoporous silica SBA15 with titanium oxide was carried out under gas phase conditions with TiCl4 as titanium source, between 473 and 673 K, followed by hydrolysis at ambient temperature. Spectroscopic characterisations (X-ray diffraction, XPS, IR, UV-Vis.) and porosimetry measurements showed that part of TiO2 is grafted on the internal surface of the pores. Catalytic activity was tested in selective oxidation of bulky alkenes. Several cycles of reaction showed that any leaching of Ti species is observed in the liquid phase.