Observation of steric hindrance in heteraferrocenophanes by carbon-13 NMR

The ¹³C NMR spectra of stereoisomeric trans- and cis-1,3-dimethyl-2-oxa[3](1, 1′)ferrocenophanes, 1,2,3-trithia[3](1, 1′)ferrocenophane and 1,3-dithia[3](1, 1′)ferrocenophane have been recorded and analysed. The presence of steric hindrance in some of these compounds was confirmed and the conformations of the molecules were determined.