Bond-shift isomers: the co-existence of allenic and propargylic phenylnitrile imines.

  title={Bond-shift isomers: the co-existence of allenic and propargylic phenylnitrile imines.},
  author={Cl{\'a}udio M. Nunes and Igor Reva and Rui Fausto and Didier B{\'e}gu{\'e} and Curt Wentrup},
  journal={Chemical communications},
  volume={51 79},
We discovered a 1,3-dipolar species co-existing in two different structures. Photolysis of matrix-isolated 5-phenyltetrazole generates two forms of phenylnitrile imine: propargylic and allenic. They are not resonance structures but correspond to different energy minima, representing bond-shift isomers. These distinct species were characterized spectroscopically and confirmed by calculations up to the CASSCF(14,12) theory level. 
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