1572001-69-4Relevant academic research and scientific papers
Iron(ii) complexes of ditopic carbanionic carbenes
Musgrave, Rebecca A.,Turbervill, Robert S. P.,Irwin, Mark,Herchel, Radovan,Goicoechea, Jose M.
, p. 4335 - 4344 (2014)
Reaction of dimesityliron(ii) (Fe2(mes)4) with the N-heterocyclic carbenes 1,3-bis(2,6-diisopropylphenyl)-imidazol-2-ylidene (IPr) and 1,3-bis(2,6-dimethylphenyl)hexahydropyrimidin-2-ylidene (6-Xyl) afforded the novel trigonal planar complexes [Fe(IPr)(mes)2] (1) and [Fe(6-Xyl)(mes)2] (2), respectively. Both species were structurally characterized by single crystal X-ray diffraction and display structures and magnetic responses consistent with a quintet ground state (S = 2). Reaction of 1 with KC8 in THF afforded K+ salts of the anionic complex [{:C[N(2,6-iPr2C6H3)] 2(CH)C}2Fe(mes)]- (3) and the homoleptic organometallic anion [Fe(mes)3]- (4). By contrast, reduction of 2 resulted in extensive decomposition and intractable product mixtures. Complex 3 is coordinated by two ditopic carbanionic carbenes via the C4/C5 position while the C2 position retains unquenched carbenic character and remains vacant for further coordination. This was corroborated by reacting solutions of 3 with one and two equivalents of triethylaluminium (AlEt 3) which resulted in the formation of [{Et3Al:C[N(2,6- iPr2C6H3)]2(CH)C}{:C[N(2, 6-iPr2C6H3)]2(CH)C} Fe(mes)]- (5) and [{Et3Al:C[N(2,6-iPr 2C6H3)]2(CH)C}2Fe(mes)] - (6), respectively. Both of these species were structurally characterized as [K(2,2,2-crypt)]+ salts.
