Journal article


KINETICALLY ENHANCED METALATION - HOW SUBSTITUENTS DIRECT ORTHO LITHIATION


Publication Details
Author(s): van Eikema Hommes N, Schleyer P
Publisher: Wiley-VCH Verlag
Publication year: 1992
Volume: 31
Journal issue: 6
Pages range: 755-758
ISSN: 1433-7851

Abstract

Not the complexation of the ground state but rather of the transition state explains the directing and activating effect of electronegative ortho substituents in the lithiation of aromatic compounds. Ab initio calculations show that the ground state of a C6H5F-LiH complex for para metalation (complexation by the benzene ring) is energetically more favorable than that for ortho metalation (complexation by F), by -12.8 vs. -12.4 kcal mol-1. In the transition state, however, the tables are turned; the respective activation barriers are +17.9 and +6.5 kcal mol-1. This is in accord with the experimental findings that only ortho-fluorolithiobenzene is formed.



How to cite
APA: van Eikema Hommes, N., & Schleyer, P. (1992). KINETICALLY ENHANCED METALATION - HOW SUBSTITUENTS DIRECT ORTHO LITHIATION. Angewandte Chemie-International Edition, 31(6), 755-758.

MLA: van Eikema Hommes, Nico, and Paul Schleyer. "KINETICALLY ENHANCED METALATION - HOW SUBSTITUENTS DIRECT ORTHO LITHIATION." Angewandte Chemie-International Edition 31.6 (1992): 755-758.

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