1509894-08-9Relevant academic research and scientific papers
Facile access to mono- and dinuclear heteroleptic N-heterocyclic silylene copper complexes
Tan, Gengwen,Blom, Burgert,Gallego, Daniel,Driess, Matthias
, p. 363 - 369 (2014)
Reaction of the heteroleptic N-heterocyclic chlorosilylene L(Cl)Si: (1; L = PhC(NtBu)2) with [Cu(tmeda)(CH3CN)][OTf] (2; tmeda = N,N,N′,N′-tetramethylethylenediamine, OTf = OSO2CF 3 (triflate)) affords the Cu(I) complex [L(Cl)Si:→Cu(tmeda)] [OTf] (3) in high yield as the first example of a heteroleptic N-heterocyclic silylene copper complex. Similarly, the reaction of L(OtBu)Si: (4; L = PhC(NtBu)2) with 2 affords [L(OtBu)Si: → Cu(tmeda)][OTf] (5) and that of L(NMe2)Si: (6) with 2 leads to [L(NMe2)Si: →Cu(tmeda)][OTf] (7). Complex 3 shows a rather strong interaction in the solid state between the O atom of the triflate anion and the three-coordinate Cu(I) center with a Cu···O distance of 2.312 A. In contrast, complex 7 features only a weak interaction (ca. 3.28 A), while in complex 5 the cation and anion are fully separated. Strikingly, the reaction of the chelating oxo-bridged silylene:Si(L)(μ2-O)(L)Si: (8) with the copper source [Cu(CH3CN)4][OTf] (9) affords the dinuclear complex salt [Cu2{η1:η1- LSi(μ2-O)SiL}2][OTf]2 (10), featuring a novel metallacyclooctane dication, selectively in a good yield. Complex 10 also exhibits a very strong interaction between the copper centers in the dication and the oxygen atoms of triflate anions in the solid state, evidenced by a Cu···O separation of only 2.141 A. All complexes were fully characterized.
