460740-91-4Relevant academic research and scientific papers
Synthesis, structures, and reactivity of mono- and bis(ferrocenyl)- substituted group 14 metallocenes
Joudat, Mounia,Castel, Annie,Delpech, Fabien,Riviere, Pierre,Mcheik, Ali,Gornitzka, Heinz,Massou, Stephane,Sournia-Saquet, Alix
, p. 3147 - 3152 (2008/10/09)
New mono- and bis(ferrocenyl)-substituted germanocenes and stannocenes have been synthesized in good yield by the reaction between group 14 dichlorides (Cl2Ge-dioxane, Cl2Sn) and the lithium salts of the corresponding mono- and bis(cyclopentadienyl)-substituted ferrocenes. The X-ray crystal structure analyses of germanocenes 3a and 4a reveal a bent sandwich structure with an angle between the cyclopentadienyl planes of 45.4° and 40.9° for 3a and 4a, respectively. Mass spectrometry and electrochemical studies show the stabilization of the generated transient cations by ferrocenyl groups, particularly in the germanium series. Their reactions with electrophilic reagents such as catechol and cycloaddition with o-quinone also are reported and show, in the latter case, an increase of the specific reactivity of the dimethylcyclopentadienyl moiety.
New linked di-germanocenes and di-stannocenes
Rouzaud,Joudat,Castel,Delpech,Rivière,Gornitzka,Manriquez,Chavez
, p. 44 - 51 (2007/10/03)
New bridged di-germanocenes and di-stannocenes 2 have been synthesized from a reaction between (pentamethylcyclopentadienyl)metal chloride and the dilithium salts of the corresponding linked cyclopentadienyl ligands (spacer: phenylene, biphenylene, thiophene) in good yields. These di-metallocenes react easily with catechol giving preferentially the substitution reaction. With iodine or with metal 14 dichloride (M = Ge, Sn), the oxidative products are unstable and rapidly loose the linked cyclopentadienyl ligand. Starting from SnCl2, the ionic half-sandwich compound [Cp*Ge][SnCl3] 8, so obtained, was characterized by X-ray diffraction analysis which reveals a polymeric form in the solid state. The reaction of the di-germanocenes with o-quinone leads to the expected cycloadducts, stable in the case of permethylated compounds. An unusual single electron transfer reaction takes place with [Cp2Fe][BF4] and the transient cation radical rapidly gives [Cp*Ge][BF4]. Mass spectra measurements and electrochemistry study confirm the weak stability of this cationic species.
