The co-catalysis of the Julia-Colonna epoxidation with selected phase transfer catalysts results in a dramatic increase of reactivity and sometimes also in a higher enantiomeric excess of the product. The required amount of polyamino acid can be significantly reduced under the new conditions, such that large scale industrial application of the method is now feasible. Highly active catalyst can be prepared via a statistical polymerisation of leucine-N-carboxyanhydride at elevated temperature. (c) 2006 Elsevier B.V All rights reserved.