The n.m.r. spectrum of tricarbonyl-(trans-1,3-dimethylindane)chromium (I; M = Cr) shows separate signals for the four aromatic protons, the separation being sufficient for the spectra to be considered first order. The aromatic regions of the spectra of other cis-tricarbonyl-(1-substituted indane)chromiums show similar properties, in contrast to the spectra of the corresponding trans-isomers. The signal separation in the case of the cis-isomers is attributed to the tricarbonylchromium residue adopting a preferred conformation in which steric interactions with the bulky cis-substituent are minimised.
|Number of pages||5|
|Journal||Journal of the Chemical Society B: Physical Organic|
|Publication status||Published - 1 Dec 1969|