1241801-28-4Relevant articles and documents
Synthesis and coordination chemistry of a new N4-Polydentate class of pyridyl-functionalized scorpionate ligands: Complexes of Fe II, ZnII, NiII, VIV, PdII and use for heterobimetallic systems
Wanke, Riccardo,Guedes Da Silva, M. Fatima C.,Lancianesi, Stefano,Silva, Telma F. S.,Martins, Luisa M.D.R.S.,Pettinari, Claudio,Pombeiro, Armando J. L.
experimental part, p. 7941 - 7952 (2010/11/17)
The new potentially N4-multidentate pyridyl-functionalized scorpionates 4-((tris-2,2,2-(pyrazol-1-yl)ethoxy)methyl)pyridine (TpmPy, (1)) and 4-((tris-2,2,2-(3-phenylpyrazol-1-yl)ethoxy)methyl)pyridine (TpmPy Ph, (2)) have been synthesized and their coordination behavior toward FeII, NiII, ZnII, CuII, Pd II, and VIII centers has been studied. Reaction of (1) with Fe(BF4)2 6H2O yields [Fe(TpmPy) 2](BF4)2 (3), that, in the solid state, shows the sandwich structure with trihapto ligand coordination via the pyrazolyl arms, and is completely low spin (LS) until 400 K. Reactions of 2 equiv of (1) or (2) with ZnII or NiII chlorides give the corresponding metal complexes with general formula [MCl2(TpmPy)2] (M = Zn, Ni; TpmPy* = TpmPy, TpmPyPh) (4-7) where the ligand is able to coordinate through either the pyrazolyl rings (in case of [Ni(TpmPy) 2]Cl2 (5)) or the pyridyl-side (for [ZnCl 2(TpmPy)2] (4), [ZnCl2(TpmPyPh) 2] (6) and [NiCl2(TpmPyPh)2] (7)). The reaction of (1) with VCl3 gives [VOCl2(TpmPy)] (8) that shows the N3-pyrazolyl coordination-mode. Moreover, (1) and (2) react with cis-[PdCl2(CH3CN)2] to give the disubstituted complexes [PdCl2(TpmPy)2] (9) and [PdCl 2(TpmPyPh)2] (10), respectively, bearing the scorpionate coordinated via the pyridyl group. Compounds (9) and (10) react with Fe(BF4)2 to give the heterobimetallic Pd/Fe systems [PdCl2(μ-TpmPy)2Fe](BF4)2 (11) and [PdCl2(μ-TpmPyPh)2Fe2(H 2O)6](BF4)4 (13), respectively. Compound (11) can also be formed from reaction of (3) with cis-[PdCl 2(CH3CN)2], while reaction of (3) with Cu(NO3)2 2.5H2O generates [Fe(μ-TpmPy) 2Cu(NO3)2](BF4)2 (12), confirming the multidentate ability of the new chelating ligands. The X-ray diffraction analyses of compounds (1), (3), (4), (5), and (9) are also reported.
