1 A Synergistic Effect of Cobalt Schiff Base Complex and TiO 2 Nanoparticles on Aerobic Olefin Epoxidation Maasoumeh Jafarpour * , Hossein Kargar, Abdolreza Rezaeifard * Catalysis Research Laboratory, Department of Chemistry, Faculty of Science, University of Birjand, Birjand, 97179-414 Iran Experimental General remarks All chemicals were purchased from Merck or Fluka. FTIR spectra were recorded on a NICOLET spectrometer. Thermogravimetric analysis (TGA) of powders was performed in air by Shimadzu 50. TEM images were obtained with a 906 E instrument (Zeiss, Jena, Germany). Samples for TEM experiment were prepared by dispersion in ethanol, sonicating for 30 min, and evaporating one drop of the solution onto a 200 mesh formbar-coated copper grid. XP spectra were recorded using a BESTEC GMBH (10 -10 mw) with Al anode. Diffuse reflectance UV–Vis spectra were recorded using an Avantes spectrometer (Avaspec-2048- TEC model). Progress of each reactions was monitored by TLC using silica-gel SIL G/UV 254 plates and also by GC on a Shimadzu GC-16A instrument using a 25 m CBP1-S25 (0.32 mm ID, 0.5 µm coating) capillary column. NMR spectra were recorded on Bruker Avance DPX 250 and 400 MHz instruments. - The Preparation of organosilicon aldehyde To a solution of (3-Chloropropyl) trimethoxysilan (0.74 mL, 4 mmol) in DMSO (0.35 mL, 5 mmol) was added NaHCO 3 (0.67 g, 8 mmol). The solution was refluxed at 155 ºC for 2 h. Then, water (50 mL) was added to the reaction mixture and the product extracted with Et 2 O (2 × 50 mL). The organic layer was separated and dried over anhydrous CaCl 2 and filtered. Evaporation of the solvent afforded the desired product (yellow oil, 70 % Isolated yield). Structural assignments of the product is based on their FT-IR, 1 H NMR [21]. - The Preparation of Schiff base ligand To a solution of (3-oxopropyl) trimethoxysilan (0.8 mL, 5 mmol) in ethanol (10 mL) was gradually added a solution of ethanol amine (0.3 mL, 5 mmol ) in ethanol (10 mL ) at 60 ºC under ultrasonic agitation. Then, the reaction mixture remained under the same conditions for 60 min. Afterwards, the product which was precipitated after 24 hoursat room temperature, Electronic Supplementary Material (ESI) for RSC Advances. This journal is © The Royal Society of Chemistry 2016