New n Ligand N,N,N,N',N',N'-Hexaallylethylenediaminium (L~(2+)): Synthesis and Crystal Structures of LBr2 · 2H2O and Its Cuprocomplexes L[Cu~(II)(Br_(0.45)Cl_(3.55))], L[Cu4(Br_(4.55)Cl_(1.45))], and L[Cu4Br6]

摘要

The alkylation of ethylenediamine with allyl bromide in the presence of a fourfold (with respect to ethylenediamine) molar amount of NaHCO3 in acetone with an ethanol admixture (15 : 1) affords LBr2 · 2H2O (I), where L~(2+) is the N,N,N,N',N',N'-hexaallylethylenediaminium cation. Single crystals of complexes L[Cu~(II)(Br_(0.45)Cl_(3.55))] (II), L[ Cu_4~I (Br_(4.55)Cl_(1.45))] (III), and L[Cu4 Br6] (IV) are prepared by ac electrochemical synthesis from an ethanolic solution of LBr2 · 2H2O, CuCl2 · 2H2O (or CuBr2) at copper wire electrodes. The crystal structures of compounds I-IV are determined by X-ray diffraction analysis. The crystals of complex I are mon-oclinic: space group P2_1, a = 8.544(3), b = 10.404(3), c = 13.350(4) A, β = 97.29(3)°, V = 1177.2(6) A~3, Z=2. The bromine anions in compound I are bonded to the L~(2+) cations and water molecules through hydrogen contacts (E)H···Br (E = O, C) of 2.57(3)-2.86(3) A. The crystals of compounds II-IV are triclinic: space group P1. For II: a = 8.762(4), b = 9.163(4), c = 16.500(6) A, α = 95.62(4)°, β = 96.39(4)°, γ= 111.46(4)°, V = 1211.4(9) A~3, Z= 2; for III: a = 9.074(4), b = 9.435(4), c = 9.829(5) A, α = 116.12(4)°, β = 104.14(4)°, γ = 100.22(4)°, V = 692.3(6) A~3, Z= 1; for IV isostructural III: a = 9.084(4), b = 9.404(4), c = 9.869(4) A, α = 116.31(3)°, β = 104.00(3)°, γ = 100.37(3)°, V= 692.1(5) A , Z= 1. Unlike the isolated tetrahedral CuX_4~(2-) anion in structure II, an original chain anion (Cu4X_6~(2-) )_n is observed in the structures of π complexes III and IV.