N-pyrrolylketene: a nonconjugated heteroarylketene.

@article{Islami2011NpyrrolylketeneAN,
  title={N-pyrrolylketene: a nonconjugated heteroarylketene.},
  author={Mohammad Reza Islami and Annette D. Allen and Sinisa Vukovic and Thomas T. Tidwell},
  journal={Organic letters},
  year={2011},
  volume={13 3},
  pages={
          494-7
        }
}
N-Pyrrolylketene (5) is calculated to be destabilized and nonconjugated, with a preferred geometry with the pyrrolyl ring orthogonal to the ketenyl group. Ketene 5 is generated from N-pyrrolylacetic acid (7) with use of Mukaiyama's reagent, and reacts with imines forming β-lactams 10, with a product ratio correlation of log(cis/trans) with σ(+). Photolysis of N-diazoacetylpyrrole (14) in MeOH gives methyl N-pyrrolylacetate (15) from 5 and also ester 17, evidently by trapping of 2-(1… Expand
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