517863-62-6Relevant articles and documents
Organometallic π-tweezers incorporating pyrazine- and pyridine-based bridging units
Al-Anber,Stein, Th.,Vatsadze,Lang
, p. 50 - 56 (2008/10/09)
The synthesis of heterobimetallic (TiCu, TiAg) and tetranuclear heterobimetallic (Ti2Ag2) transition metal complexes based on the organometallic π-tweezer building blocks [Ti](CCSiMe 3)2 is described. In [{[Ti](μ-σ,π-CCSiMe 3)2}M-LL]+ and [{[Ti](μ-σ,π- CCSiMe3)2}MLLM{(Me3SiCC-μ-σ,π) 2[Ti]}]2+ (M = Cu, Ag; LL = pyrazine- or pyridine-based bridging units) the metal containing parts are spanned by π-conjugated organic bridges LL. Depending on the nature of LL coordination polymers are also accessible. Pyrazine- and pyridine-based π-conjugated σ-donor molecules, such as 4,4′-bipyridine, 1,2-di(4-pyridyl)ethylene, 3,5-dipyridyl-1,2,4-triazole, N,N′-bis(4-pyridylmethylidene)benzene-1,4- diamine, 2,5-di(pyridylmethylidene)cyclopentanone, 2,6-di(4-pyridylmethylidene) cyclohexanone (LL, 2a-2g) can successfully be used to span heterobimetallic π-tweezer units of the type [{[Ti](μ-σ,π-CCSiMe3) 2}M]+ ([Ti] = (η5-C5H 4SiMe3)2Ti; M = Cu, Ag). The thus accessible di-cationic species [{[Ti](μ-σ,π-CCSiMe3) 2}MLLM{(Me3SiCC-μ-σ,π)2[Ti]}] 2+ (4), which are formed via the formation of [{[Ti](μ-σ, π-CCSiMe3)2}MLL]+ (3) complexes, can be isolated in yields between 66% and 99%. However, when C5H 4NCHCHC6H4CHCHNC5H4 (5a) and C5H4NCHNC6H4CHCHNC 5H4 (5b), respectively, are reacted with {[Ti](μ-σ,π-CCSiMe3)2}AgBF4(1c) in a 1:1 molar ratio, then the silver(I) ion is released from the organometallic π-tweezer 1c and coordination polymers [AgBF4 ? 5a] n (6a) and [AgBF4 ? 5b]n (6b) along with [Ti](CCSiMe3)2 (7) are formed in quantitative yield.
