Communication
ess: oxidative addition, alkyne amination and reductive elimina- ess and an expansion of the scope of this process an important
tion. The putative intermediate 19 can undergo reductive elimi- subject of future work.
nation, while the formation of an analogous intermediate in
Equation 4 seems to be problematic.
Acknowledgments
The Natural Science and Engineering Research Council (NSERC)
of Canada is acknowledged for some financial support for this
project (Discovery, CREATE Sustainable Synthesis program). The
Department of Chemistry at the University of British Columbia
is thanked for financial support of this program. We acknowl-
edge Dr. Brian O. Patrick for X-ray crystallographic analysis, and
Dr. Yun Ling for technical assistance in the acquisition of mass
spectrometry data.
Keywords: Nickel · Catalysis · Indole · Alkyne addition ·
Methods
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Conclusion
In summary, nickel complexes ligated to d(Cy)pf can catalyze
an arylative addition to 2-alkynyl-N-arylsulfonylanilides to form
2,3-disubstituted indoles. Compared to a cross-coupling be-
tween an aryl halide and an organometallic, this reaction re-
quires a careful partitioning between the desired process and
several undesired reactions involving the alkyne function of the
2-alkynyl-N-sulfonylanilide starting material. Even so, the effi-
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