2,5-Bis(pyridyl) pyrazine PtM, Pt2M and Ti2M2 transition metal complexes (M = Cu, Ag)

作者：Al Anber Mohammed; Wetzold Nora; Walfort Bernhard; Rueffer Tobias; Lang Heinrich^*

来源：Inorganica Chimica Acta, 2013, 398: 124-131.

DOI：10.1016/j.ica.2012.12.023

• Organometallic pi-tweezer
• 2,5-Bis(pyridyl) pyrazine
• Copper
• Silver platinum
• Titanium

The synthesis, properties and characterization of a series of 2,5-bis(pyridyl) pyrazine-based heterobi( PtM) (5, 6) , tri-(Pt2M) (8) and tetra-nuclear (Ti2M2) (10) (M = Cu, Ag) transition metal complexes is reported using [(bppz) Pt(C, CSiMe3)(2)] (2) (bppz = 2,5-bis(pyridyl) pyrazine) , {[Ti](mu-sigma, p-C, CSiMe3) (2)} MX (9a, M = Cu, X = FPF5; 9b, M = Ag, X = OClO3; [Ti] = (eta(5)-C5H4SiMe3)(2)Ti) and diverse copper(I) and silver(I) salts as key starting materials. Treatment of 2 with equimolar amounts of [Cu(N, CMe) 4] X (3a, X = BF4; 3b, X = OTf(@ OSO2CF3) ) or [MX] (M = Cu: 3c, X = Br; M = Ag: 4a, X = ClO4; 4b, X = O(2)CCF3; 4c, X = NO3) gave heterobimetallic [(bppz) Pt((mu-sigma, p-C, CSiMe3)(2)MX) ] (M = Cu: 5a, X = FBF3; 5b, X = OTf; 5c, X = Br. M = Ag: 6a, X = OClO3; 6b, X= O2CCF3; 6c, X = ONO2) , while a 1: 2 stoichiometry of, for example, 2: 3a and 2: 4a, respectively, produced trimetallic {[(bppz) Pt(l-r, p-C, CSiMe3)(2)] 2M} X (8a, M = Cu, X = BF4; 8b, M = Ag, X = ClO4) . Molecules 8a and 8b are also accessible, when 5a or 6a were reacted with 2 in a 1: 1 molar ratio. In 8a and 8b two (bppz) Pt(C, CSiMe3)(2) tweezer moieties are connected by M+ ions thus resulting in a pseudo-tetrahedral environment about M+. Complexes of general composition [([Ti](mu-sigma, pC, CSiMe3)(2)M)(2)(bppz) ][X] (2) (10a, M = Cu, X = PF6; 10b, M = Ag, X = ClO4) were accessible by treatment of {[Ti]mu-sigma, p-C, CSiMe3)(2)} MX (9a, M = Cu, X = FPF5; 9b, M = Ag, X = OClO3) with 0.5 equivalents of bppz. The structure of 10b in the solid-state shows that bppz acts as connectivity for the bridging of two {[Ti]((mu-sigma, p-C, CSiMe3)(2)) Ag}+ building blocks, whereby the planar bppz unit is almost perpendicular oriented towards the Ti-Ag organometallic p-tweezer groups. Cyclic voltammetry measurements reveal that upon reduction of 5, 6 and 10 decomposition of these complexes occurs upon formation of elemental M and non-coordinated (bppz) Pt(C, CSiMe3)(2) and [Ti](C, CSiMe3)(2), respectively.

• 出版日期2013-3-24