First Allylpalladium Systems Containing Chiral Imidazolylpyridine Ligands – Structural Studies and Catalytic Behaviour

Abstract

Abstract Palladium/chiral imidazolylpyridine systems were tested in allylic alkylation of rac ‐3‐acetoxy‐1,3‐diphenyl‐1‐propene ( rac ‐ I ) and 3‐acetoxy‐1‐phenyl‐1‐propene ( II ), paying particular attention to the influence of the amine nitrogen hybridisation on their catalytic behaviour. Allylpalladium complexes 9 – 11 containing optically pure imidazolines were synthesised and fully characterised both in solution (NMR) and the solid state (single‐crystal X‐ray diffraction). NMR studies showed four species in solution for complex 9 containing the unsymmetrical 1‐phenylallyl group, while for 10 and 11 , involving the symmetrical 1,3‐diphenylallyl moiety, two species, endo and exo , were identified. In the solid state, only endo isomers crystallised for each complex. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)