New Pd(II) Complexes with 4-Methylamino-3-Penten-2-One CH3C(NHCH3)CHC(O)CH3

Abstract

The crystal structures of two new palladium complexes with 4-methylamino-3-penten-2-one CH₃C(NHCH₃)CHC(O)CH₃ (Hmki) are determined. The crystals β-trans-Pd(mki)₂ (1) and Pd(ki) (mki)·0.5(C₆H₆) (2) (ki = CH₃C(NH)CHC(O)CH₃, mki = CH₃C(NCH₃)CHC(O)CH₃). The crystals belong to the triclinic system with the following unit cell parameters for 1: space group \(P\bar{1}\), a = 7.1877(3) Å , b = 7.2668(4) Å, c = 7.3246(3) Å, α = 83.903(1)°, β = 61.263(1)°, γ = 74.197(1)°, V = 322.64(3) Å³, Z = 1; for 2: space group \(P\bar{1}\), a = 7.1787(2) Å, b = 9.4578(4) Å, c = 12.1817(7) Å, α = 108.361(1)°, β = 96.160(1)°, γ = 107.046(1)°, V = 732.09(6) Å³, Z = 2. The complexes have molecular structures composed of isolated Pd(mki)₂ and Pd(ki)(mki) molecules in 1 and 2 respectively. The electron density distribution in α-trans-Pd(mki)₂, β-trans-Pd(mki)₂ (1) and mixed-ligand Pd(ki)(mki)·0.5(C₆H₆) (2) complexes is studied by quantum chemical calculations using the density functional theory. The topological analysis reveals that the electron density distributions are similar in both α- and β-trans-Pd(mki)₂ complexes. Based on the analysis of intermolecular interactions it is shown that different molecular geometries of the α and β modifications of trans-Pd(mki)₂ results in differences in structure-forming intermolecular contacts and consequently, affects the crystal molecular packing.