Characterization of molecular structure of DAST via NMR spectroscopy

• 1H NMR, 13C NMR, 1H–1H COSY, 1H–13C HSQC and 1H–13C HMBC spectra of DAST in CD3OD were obtained.
• All peaks in 1H and 13C NMR spectra of DAST were assigned.
• The mistake and uncertainty in the reported assignments of peaks in 1H NMR spectra of DAST were corrected.

4-N, N-dimethylamino-4′-N′-methyl-stilbazolium tosylate (DAST) crystal has excellent properties of nonlinear optics and electro-optical effect, and it can be used in the fields of radiation and detection through wave bands from infrared to terahertz. Besides, DAST thin films have exhibited their excellent properties and have expanded application fields of DAST material. CD3OD was chosen as the solvent to conduct 1H NMR, 13C NMR, 1H–1H COSY, 1H–13C HSQC and 1H–13C HMBC characterization of DAST respectively. All peaks in 1H and 13C NMR spectra of DAST were assigned with assistance of 2D NMR correlation peaks.