Hydrodehalogenation of Aryl Chlorides and Aryl Bromides Using a Microwave-Assisted, Copper-Catalyzed Concurrent Tandem Catalysis Methodology
A concurrent tandem catalytic methodology has been developed for the hydrodehalogenation of aryl bromides and aryl chlorides. The first step of the tandem catalytic cycle, halogen exchange, produced yields of 84–97% from aryl bromides using 5 mol % CuI catalyst, 10 mol % N,N′-dimethylcyclohexane-1,2...
Saved in:
Published in | Organometallics Vol. 30; no. 15; pp. 4067 - 4073 |
---|---|
Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
American Chemical Society
08.08.2011
|
Online Access | Get full text |
Cover
Loading…
Summary: | A concurrent tandem catalytic methodology has been developed for the hydrodehalogenation of aryl bromides and aryl chlorides. The first step of the tandem catalytic cycle, halogen exchange, produced yields of 84–97% from aryl bromides using 5 mol % CuI catalyst, 10 mol % N,N′-dimethylcyclohexane-1,2-diamine (1), and 2 equiv of NaI in acetonitrile under microwave radiation at 100 °C in 0.5–1.5 h. The same reaction for aryl chlorides appeared to be equilibrium-limited after 1 hour at 200 °C (yields of 5–44%). Both aryl bromides and aryl chlorides were hydrodehalogenated in 12–87% yield using 20 mol % CuI, 1.5 equiv of diamine 1, and 2 equiv of NaI in acetonitrile at 200 °C after 1–2 h. Substrates with oxygen- or nitrogen-containing functional groups had substantially lower yields than hydrocarbon substrates. Deuterium labeling studies suggest that diamine 1 supplies the majority of the hydrogen for the hydrodehalogenation reaction, but solvent can also serve as a source. |
---|---|
ISSN: | 0276-7333 1520-6041 |
DOI: | 10.1021/om2003706 |