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Functionalizations of Mixtures of Regioisomeric Aryllithium Compounds by Selective Trapping with Dichlorozirconocene.

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.

SUBMITTER: Castello-Mico A

PROVIDER: S-EPMC6680335 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Functionalizations of Mixtures of Regioisomeric Aryllithium Compounds by Selective Trapping with Dichlorozirconocene.

Castelló-Micó Alicia A Herbert Simon A SA León Thierry T Bein Thomas T Knochel Paul P

Angewandte Chemie (International ed. in English) 20151120 1

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 ...[more]

PMID: 26586204

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