Characterization of Molecular Structure of DAST Using Nuclear Magnetic Resonance Spectroscopy

doi:10.11938/cjmr20150409

Abstract

Abstract:

DAST crystal (4-N, N-dimethylamino-4’-N’-methyl-stilbazolium tosylate crystal) shows electro-optical effect, and has excellent properties for second-order nonlinear optics. It can be used for wave radiation and detection from infrared to terahertz range. In this study, the molecular structure and purity of DAST crystal were analyzed by liquid-state NMR spectroscopy (i.e., ¹H NMR, ¹³C NMR, ¹H-¹H COSY, HSQC and HMBC) using CD₃OD and DMSO-d₆ as solvents. It was observed that DAST tended to exist in the form of ion pair in CD₃OD solution, while in the form of dissociative state in DMSO-d₆solution. This could be due to solvent-dependent redistribution of electron cloud in the conjugated structure and movement of the framework.

Key words: liquid-state NMR, assignment, two-dimensional NMR, DAST, terahertz

CLC Number:

O482.53

PANG Zi-bo*， MENG Da-lei， DOU Ying， MA Si-rui， WU Cong，CHENG Hong-juan， XU Yong-kuan. Characterization of Molecular Structure of DAST Using Nuclear Magnetic Resonance Spectroscopy
[J]. Chinese Journal of Magnetic Resonance, 2015, 32(4): 637-647.

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