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Updated: Mar 30, 2026

Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
Functionalizations of Mixtures of Regioisomeric Aryllithium Compounds by Selective Trapping with Dichlorozirconocene
Alicia Castelló-Micó1, Simon A Herbert1, Thierry León1
1Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, Haus F, 81377 München (Germany).
Abstract:
The reaction of mixtures of aryllithium regioisomers obtained either by directed lithiation or by Br/Li exchange with substoichiometric amounts of Cp2ZrCl2 proceeds with high regioselectivity. The least sterically hindered regioisomeric aryllithium is selectively transmetalated to the corresponding arylzirconium species leaving the more hindered aryllithium ready for various reactions with electrophiles. As an application, these regioselective transmetalations from Li to Zr were used to prepare all three lithiated regioisomers of 1,3-bis(trifluoromethyl)benzene.
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