The clay surface plays a role in the enantioselectivity of the cyclopropanation reaction, in the case of copper catalysts immobilized on laponite by electrostatic interactions. The effect is different depending on the type of chiral ligand, bis(oxazoline) or pyridineoxazoline. In the first case the clay promotes a reversal of the stereochemical course of the reaction. The pyridineoxazoline-copper complexes lead to very low enantioselectivity in homogeneous phase. However, the asymmetric induction increases when the complexes are immobilized on laponite, showing that it is possible to design good chiral ligands specific for the use in immobilized catalysts. (C) 2002 Elsevier Science B.V. All rights reserved.