A Dual Palladium and Copper Hydride Catalyzed Approach for Alkyl-Aryl Cross-Coupling of Aryl Halides and Olefins.
We report an efficient means of sp2 -sp3 cross coupling for a variety of terminal monosubstituted olefins with aryl electrophiles using Pd and CuH catalysis. In addition to its applicability to a range of aryl bromide substrates, this process was also suitable for electron-deficient aryl chlorides, furnishing higher yields than the corresponding aryl bromides in these cases. The optimized protocol does not require the use of a glovebox and employs air-stable Cu and Pd complexes as precatalysts. A reaction on 10 mmol scale further highlighted the practical utility of this protocol. Employing a similar protocol, a series of cyclic alkenes were also examined. Cyclopentene was shown to undergo efficient coupling under these conditions. Lastly, deuterium-labeling studies indicate that deuterium scrambling does not take place in this sp2 -sp3 cross coupling, implying that β-hydride elimination is not a significant process in this transformation.
['Friis|Stig D|SD|0000-0003-4330-5173', 'Pirnot|Michael T|MT|', 'Dupuis|Lauren N|LN|0000-0001-9915-8737', 'Buchwald|Stephen L|SL|0000-0003-3875-4775']
D000475:Alkenes D002384:Catalysis D003300:Copper D003517:Cyclopentanes D003903:Deuterium D006219:Halogens D007202:Indicators and Reagents D010084:Oxidation-Reduction D010165:Palladium
palladium copper cross-coupling alkenes homogeneous catalysis