Comparative Study of 1,5-Dinitrogen Schiff Bases as Potential Ligands in Palladium-Catalyzed Allylic Alkylation

1-(2'-Pyrido and 2'-quinolino)-(1R)-arylethylamino)-ethylidenes (7–12) were prepared as potential ligands in PdII catalytic complexes for enantioselective allylic alkylation of 1,3-diphenyl-1-acetoxy-propene-2 (15). Alkylation with palladium complexes of 7–12 yielded 1,3-diphenyl-1-dimethylmalonyl-propene-2 (14) with enantioselectivity up to 55 % e.e. Enantioselectivity is discussed in view of the results recently reported for structurally related 1,5-bidentate dinitrogen ligands of C1 symmetry. Reversal of enantioselectivity observed for the ligands 10 and 11 is attributed to the inversion of steric requirements in the second coordination sphere of their catalytic complexes.