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An Efficient and General Method for the Heck and Buchwald–Hartwig Coupling Reactions of Aryl Chlorides
The β-diketiminatophosphane Pd complex acted as a powerful catalyst for the Heck coupling of aryl chlorides with alkenes. Various aryl and heteroaryl chlorides were coupled efficiently under relatively mild conditions. Furthermore, this catalytic system also proved to be highly active in the Buchwald–Hartwig coupling of deactivated and sterically hindered aryl chlorides at room temperature.
This paper by Jin et al. (Inha University, South Korea) shows the results for the Heck and Buchwald-Hartwig coupling of non activated aryl and heteroaryl chlorides. The trick is using a special catalyst, a b-diketiminatophosphane palladium complex. This complex is not commercial, but is synthetized easily in three steps from 2,4-diketopentane. The authors report 32 examples of the Heck coupling and 9 examples of the Buchwald-Hartwig amination, all with excellent results on all type of substrates, including heterocycles. What I miss are examples of cloroarenes with another halide, that is, bromochloroarenes and chloroiodoarenes, so we can see selectivity of the reaction (it is not commented on the paper) and assess if you can have an orthogonally activated arene for couplings using two different catalytic systems. Hmmm….