Unprecedented regiochemical control in the formation of aryl[1,2-a]imidazopyridines from alkynyliodonium salts: mechanistic insights.

@article{Dixon2013UnprecedentedRC,
  title={Unprecedented regiochemical control in the formation of aryl[1,2-a]imidazopyridines from alkynyliodonium salts: mechanistic insights.},
  author={Luke I. Dixon and Michael A. Carroll and Thomas J. Gregson and George John Ellames and Ross W. Harrington and William Clegg},
  journal={Organic \& biomolecular chemistry},
  year={2013},
  volume={11 35},
  pages={
          5877-84
        }
}
Aryl(alkynyl)iodonium salts have been demonstrated to be valuable precursors to a diverse range of heteroaromatic ring systems including aryl[1,2-a]imidazopyridines. Successful application, using the recently described aryl(alkynyl)iodonium trifluoroacetate salts, is described, highlighting for the first time that the regioselectivity of this process is both counter-ion and concentration dependent. Studies with a carbon-13 labelled substrate established that the reactions of alkynyliodonium… 
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