A highly efficient heterogeneous ruthenium-catalysed oxidative α-cyanation of tertiary amines leading to α-aminonitriles

Oxidative alpha-cyanation of tertiary amines was achieved by using an MCM-41-immobilised N-alkylethylenediamine ruthenium(III) complex (MCM-41-2N-RuCl3) as catalyst in MeOH at 60 degrees C in the presence of H2O2 as oxidant and NaCN in acetic acid as a cyanide source to afford the corresponding alpha-aminonitriles in good yields. The new heterogeneous ruthenium catalyst can easily be prepared by a simple two-step procedure from commercially readily available and inexpensive reagents. It can be recovered by filtration of the reaction solution and reused at least 7 times without significant loss of activity.