[H(OEt2)(2)][B{C6H3(m-CF3)(2)}(4)] has been straightforwardly prepared through a one pot reaction. The product has been characterized by elemental and thermogravimetric analysis, H-1, C-13 NMR and IR spectroscopy. The catalytic activity of the acid in the polymerization of isobutene has been studied. Polymerizations were performed at a temperature interval from 0 to 30 degrees C. The catalytic results show conversions between 34 and 88% and between 84 and 92% in about 30 min for complexes [H(OEt2)(2)][B{C6H3(m-CF3)(2)}(4)] and [H(OEt2)(2)][B(C6F5)(4)], respectively. (C) 2014 Elsevier B.V. All rights reserved.