Synthesis and structure of chiral palladium(II) complexes bearing ethylene-bridged bisindolinyl- and bis(1,2,3,4-tetrahydroquinolinyl) ligands

A series of new neutral and cationic palladium(II) complexes of type [Pd(L-L)X(2)] (5, 6, 9, 10), [Pd(L-L)Y-2](BF4)(2) (7, 8, 11, 12) and [Pd(eta(3)-C6H9)(L-L)](PF6) (13, 14), (L-L = 1,2-bis(N-indolinyl)ethane (BIE, 3), 1,2-bis( N-1,2,3,4-tetrahydroquinolinyl)ethane (BTQE, 4); X = Cl, NO3; Y = MeCN, H2O) have been prepared and characterized. These investigations show that BIE and BTQE can lead to chiral C-2-symmetric complexes, as well as to the achiral meso compounds, A nearly quantitative yield of the C-2-symmetric isomer was found for the reaction of (PhCN)(2)PdCl2 with BIE and BTQE. The solid state structures of the C-2-symmetric [Pd(BIE)Cl-2] (5a) and the meso isomer of [Pd(eta(3)-C6H9)(BIE)](PF6) (13b) have been determined by X-ray structure analysis.