100229-33-2Relevant academic research and scientific papers
Carboxysilanes and -germanes. 5. Copper(II) complexes of carboxysilanes and -germanes: Structure and magnetic properties. Crystal structure of tetrakis(μ-phenyldimethylsilanecarboxylato)bis[aquocopper(II)]2
Steward, Omar W.,McAfee, Richard C.,Chang, Shih-Chi,Piskor, Stephen R.,Schreiber, William J.,Jury, C. Frederick,Taylor, Charles E.,Pletcher, James F.,Chen, Cheng-San
, p. 771 - 777 (2008/10/08)
Copper(II) complexes of carboxysilanes and -germanes have unusually small magnetic moments at ambient temperature. A singlet-triplet energy separation, |-2J| = 1000 ± 150 cm-1, determined by variable-temperature ESR studies on three complexes, [Cu(O2CSiR3)2·H2O] 2 (R = Ph, Me), is much larger than has been reported previously for copper(II) carboxylates. The structure of [Cu(O2CSiPhMe2)2·H2O] 2 has been determined to be of the copper(II) acetate monohydrate type, which crystallizes in the triclinic space group P1 with Z = 2, a = 14.067 (6) A?, b = 11.952 (3) A?, c = 14.147 (9) A?, α = 90.33 (4)°, β = 130.80 (4)°, and γ = 68.91 (2)°. Structural refinement led to the introduction of two conformers (1:1) that differ by rotation about trans Si-C bonds. The Cu2(CO2)4 cage shows considerable distortion from D4h symmetry. Magnetic susceptibility studies, molecular weight determinations, and 1H NMR studies all indicate that the dimer structure is maintained in solution. The enhanced exchange coupling in the copper(II) complexes of carboxysilanes and -germanes is explained in terms of σ and π interactions between the metalloid and the carboxylate group.
