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Carbon-13 n.m.r. characterization of indenyllithium in solution

✍ Scribed by Ulf Edlund

Publisher
John Wiley and Sons
Year
1977
Tongue
English
Weight
286 KB
Volume
9
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

^13^C N.m.r. chemical shifts obtained for indenyl‐ and cyclopentadienyllithium in several, mostly ethereal, solvents are presented. The chemical shift changes induced by varying the solvent are assumed to probe the actual π‐electron density distribution, thus providing an insight into the structure of the ion‐pair. The increase in the estimated π‐electron densities obtained for the protonated aromatic carbons of indenyllithium by increasing the coordinating ability of the solvent gives evidence of a change of the ion‐pair equilibrium towards solvent‐separated species. The average chemical shifts for indenyl‐ and cyclopentadienyllithium were independent of the choice of solvent, a fact which supports the ion‐pair model in all studied media.

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