Synthesis and Properties of 1-Methyl-4-{2-[4-(dimethylamino)phenyl]ethenyl}pyridinium p-Toluenesulfonate Derivatives with Isomorphous Crystal Structure

DAST, 1-methyl-4-{2-[4-(dimethylamino)phenyl]ethenyl}pyridinium p -toluenesulfonate, has been recently reported as an efficient THz-wave generator by difference frequency generation. In this study, two DAST derivatives, i.e., perdeuterated DAST (DAST- d 26 ) and DASC with p -chlorobenzenesulfonate replacing the p -toluenesulfonate of DAST, were investigated as model compounds to analyze the THz-wave intensity variation of DAST as a function of frequency. X-ray crystallographic analyses of DAST- d 26 and DASC were carried out for the first time, and it was found that both compounds gave crystals isomorphous with DAST. Their basic properties were also investigated.