The13C NMR and electronic effects in the ?-cyclopentadienyl derivatives of iron

Studies of the bonding in iron(II) cyclopentadienyl and arene sandwich compounds. Part 2. Correlations and interpretations of carbon-13 and iron-57 nuclear magnetic resonance and iron-57 mössbauer data

“…as 'the contribution to AEQ of carbons closer to the iron is balanced by different contributions of more remote carbons'.20 This implies that the q-C5H5 rings were tilted about their centres. While the excellent agreement between calculated and experimental data suggests that the actual model used has much to commend it, this particular type of tilt is unlikely to appear in a mono [3]-bridged ferrocenyl derivative and the tilt angles are also greater than 6" (see above).…”

“…Ferrocenophanes. Of the five bridged species considered three are neutral [3]ferrocenophanes (28-30), one a [3]ferrocenophanyl cation (26) and one a [4]ferrocenophane (27). There are two known crystal structures 2 3 3 2 4 of [3]ferrocenophanes including 30.…”

“…Both experimental data 2 5 and calculations 2 o have shown there to be a decrease in q.s. with increasing number of [3] bridges, due to changes in both valence and lattice-overlap contributions to the field gradients. However, ring tilt was not invoked as being responsible for these reductions and, in the calculations, a nontilting model was used.…”

N-ferrocenyl isonicotinamide, a redox-active 1D hydrogen-bonded chain structure capable of supporting a mixed-valent redox state

“…S3) NMR spectra are consistent with its proposed structure. The 1 H chemical shifts for the monosubstituted ferrocene ring are similar to that for N-ferrocenyl acetamide [7] and other monosubstituted ferrocenes [8,9]. No evidence of distinct signals for cis/trans rotamers is evident from the NMR spectra.…”

Boron trifluoride etherate as a catalyst in acylation of ferrocene

“…For this new compound, we made tentative assignments based on the spectra of related structures such as vinyl ferrocene [36] and some ferrocenyl chalcones [37]. propionyl ferrocene 5 e ) 23 79 -81 e ) 6 0 a ) 2 hours of reflux, 55%; 3.5 hours of reflux, 75%.…”