摘要 :
Two new non-innocent ligands, H2LOPh and H2LSPh, were synthesized. Both ligands reacted with 0.5 equiv. of CuCl2 center dot 2H(2)O to provide the corresponding mononuclear diradical-containing Cu-II complexes[Cu(L-OPh(SQ))(2)](1) ...
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Two new non-innocent ligands, H2LOPh and H2LSPh, were synthesized. Both ligands reacted with 0.5 equiv. of CuCl2 center dot 2H(2)O to provide the corresponding mononuclear diradical-containing Cu-II complexes[Cu(L-OPh(SQ))(2)](1) and[Cu(L-SPh(SQ))(2)] (2). Both complexes were characterized by single-crystal X-ray diffraction measurements. Molecular structure analyses indicated that, in complex 1, the two -OPh groups of two [L-OPh(SQ)](-) ligands are situated trans to each other, while in complex 2, the two - SPh groups of two [L-SPh(SQ)](-) ligands were found to maintain a cis relationship. In complex 1, Cu-C-Ph interactions as well as two pi-pi interactions were observed between -OPh-group-containing C-6 phenyl rings and the radical-containing coordinated chelate rings. In complex 2, Cu-CPh interactions were ab-sent, although intramolecular pi-pi interactions within one of the two coordinating ligands were present. The pi-pi interactions were between the C-6 phenyl ring of an -SPh group and the 3,5-di-tert-butyl-amidophenolate unit. Variable-temperature magnetic susceptibility measurements indicated that both complexes acquire an S = 1/2 ground state. X-band EPR measurements confirmed that the unpaired electron is on the CuII center in both complexes. This implies that the expected Cu-II-S secondary interactions in complex 2 are suppressed by the dominating pi-pi stacking interactions, and the ground-state electronic configuration was found to be (up arrow up arrow down arrow) instead of the expected (up arrow down arrow up arrow).
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摘要 :
An azide (-N-3) group attached at the -ortho carbon atom to the aniline moiety of 2-anilino-4,6-di-tert-butylphenol formed a diradical-containing Co(II) complex via inter-ligand azo (N=N) bond formation. Metal-to-ligand (azo), d p...
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An azide (-N-3) group attached at the -ortho carbon atom to the aniline moiety of 2-anilino-4,6-di-tert-butylphenol formed a diradical-containing Co(II) complex via inter-ligand azo (N=N) bond formation. Metal-to-ligand (azo), d pi-to-p pi* back donation stabilized the metal in its lower oxidation state.
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