Four membered chelate aminoalkyl and aminoalkenyl complexes of platinum(II). The molecular and crystal structure of [ [formula omitted]Me 2Cl(PPh 3)] and [ [formula omitted]Me 2Cl(PPh 3)

Abstract

Single-crystal x-ray diffraction structure determinations have been performed on two platinum(II) complexes containing a cyclometallated four-membered ring: [ PtCH 2CH 2N Me 2Cl(PPh 3)] (I) and [ PtC(=CMe 2)CH 2N Me 2Cl(PPh 3)] (II). The crystal data are as follows: for complex I, space group monoclinic, P2 1 / n, a = 9.488(8) Å, b = 19.320(6) Å, c = 11.913(4) Å, β = 97.63(7)°, Z = 4; for complex II, space group monoclinic, P2 1 / a, a = 19.231(6) Å, b = 12.023(5) Å, c = 10.256(4) Å, β = 95.60(6)°, Z = 4. The structures were solved by conventional Patterson, Fourier, and full matrix least-squares refinement techniques. The final consistency indices R and R w are 0.049 and 0.062 (complex I, 2946 independent reflections), and 0.036 and 0.055 (complex II, 3437 independent reflections). Both compounds show the usual square-planar arrangement of the ligands, somewhat distorted by the presence of the four-membered ring which markedly deviates from planarity. The PtC bond length, the CPtN bond angle and the puckering of the ring are 2.055(11) Å, 70.6(4)°, and 8.3° for complex I, and 2.002(7) Å, 68.6(3)°, and 25.2° for complex II respectively.