Cu/Oxalic Diamide-Catalyzed Coupling of Terminal Alkynes with Aryl Halides
Ying Chen1, Sailuo Li1, Lanting Xu2
1School of Physical Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai 201210, China.
Abstract:
N1-(2,6-Dimethylphenyl)-N2-(pyridin-2-ylmethyl)oxalamide (DMPPO) was revealed to be a more effective ligand for copper-catalyzed coupling reaction of (hetero)aryl halides with 1-alkynes than previously reported ones. Only 3 mol % CuCl and DMPPO are required to make the coupling complete at 100 °C (for bromides) and 80 °C (for iodides). Both (hetero)aryl and alkyl substituted 1-alkynes worked well under these conditions, leading to the formation of internal alkynes in great diversity.
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