A manganese-based hybrid mesoporous material (denoted as 5) was synthesized by covalent grafting of [Mn-II(1)(2)](OAc)(2) (3) (1 = [3-(2-pyridyl)pyrazol-1-yl]acetic acid amide) onto the surface of SBA-15, and characterized by means of XRD, N-2 adsorption-desorption, FT-IR, Raman, EPR and UV-vis spectroscopic techniques. Catalytic tests showed that 5 could act as an efficient heterogeneous catalyst for the epoxidation of a wide range of alkenes (including terminal ones) under mild reaction conditions when peracids (e.g., meta-chloroperbenzoic acid) are used as oxidants. Moreover, the catalytic performance of 5 is solvent-dependent, it exhibits higher catalytic activity and selectivity to epoxides when the reaction is carried out in aprotic solvent like CH3CN. UV-vis and electrochemical measurements revealed that high-valent Mn species are easily formed during the reaction course, when meta-chloroperbenzoic acid is used as oxidant and CH3CN is used as solvent, being probably the main reason for the high activity of 5 and its selectivity toward epoxide formation. (C) 2011 Elsevier B.V. All rights reserved.