Highly efficient reagents for Br/Mg exchange

Angewandte Chemie - International Edition

Volumn 45, Issue 1, 2005, Pages 159-162

  Krasovskiy, Arkady ^a   Straub, Bernd F ^a   Knochel, Paul ^a  

^a UNIVERSITY OF MUNICH   (Germany)

Author keywords

Bromine magnesium exchange; Density functional calculations; Grignard reaction; Lithium; Schlenk equilibrium

Indexed keywords

BROMINE; LITHIUM; MAGNESIUM PRINTING PLATES; MATHEMATICAL MODELS; PROBABILITY DENSITY FUNCTION; QUANTUM THEORY; REACTION KINETICS;

BROMINE-MAGNESIUM EXCHANGE; GRIGNARD REACTION; SCHLENK EQUILIBRIUM;

ION EXCHANGE;

EID: 29344432351     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.200502220     Document Type: Article

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31. 2Mg·LiCl (1M in THF) were also prepared and applied in Br/Mg-exchange reactions with 3. However, these tert-butylmagnesiates featured slightly lower reaction rates than the secondary reagents 1 and 14. For full conversion of the aryl bromides into the Grignard reagents, 1.1 equiv of both types of reagents was enough, therefore indicating that no elimination of HBr from the tBuBr byproduct by magnesiates takes place. Further work on magnesiates with different alkyl groups is in progress in our laboratories.