97535-93-8Relevant articles and documents
Anisotropy Effects of Conjugated Cyclic Systems, VI. Structure and Magnetic Anisotropy of Mesityl-substituted Ferrocens
Fuchs, Bernhard,Froehlich, Roland,Musso, Hans
, p. 1968 - 1982 (2007/10/02)
Two isomeric ferrocene derivatives have been obtained from 2-(2-ethyl-4,6-dimethylphenyl)-1,3-dimethylcyclopentadiene (22a).The exo,exo- (9) as well as the endo,endo-configuration (10) of these were determined by X-ray structure analysis.The assignment of the 1H NMR signals of the methyl groups in the spectrum of 1,1',3,3'-tetramethyl-2,2'-dimesitylferrocen (7) is derived from the spectra of 9 and 10.Signals of methyl groups in exo-position of the mesitylferrocene are shifted by -0.74 ppm to higher magnetic field.Signals of methyl groups in endo-position directed towards the iron atom are shifted downfield by +0.71 ppm.Therefore, ferrocene develops a diamagnetic anisotropy which is similar to that of benzene.