Benzoxazine oligomers: evidence for a helical structure from solid-state NMR spectroscopy and DFT-based dynamics and chemical shift calculations.

@article{Goward2003BenzoxazineOE,
  title={Benzoxazine oligomers: evidence for a helical structure from solid-state NMR spectroscopy and DFT-based dynamics and chemical shift calculations.},
  author={Gillian R. Goward and Daniel Sebastiani and Ingo Schnell and Hans W. Spiess and Ho-Dong Kim and Hatsuo Ishida},
  journal={Journal of the American Chemical Society},
  year={2003},
  volume={125 19},
  pages={
          5792-800
        }
}
A combination of molecular modeling, DFT calculations, and advanced solid-state NMR experiments is used to elucidate the supramolecular structure of a series of benzoxazine oligomers. Intramolecular hydrogen bonds are characterized and identified as the driving forces for ring-shape and helical conformations of trimeric and tetrameric units. In fast MAS (1)H NMR spectra, the resonances of the protons forming the hydrogen bonds can be assigned and used for validating and refining the structure… 
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