86100-84-7Relevant academic research and scientific papers
The π-π interactions enhanced in salicylaldimines and salicylaldazines
Kuo, Hsiu-Ming,Hsu, Yu-Te,Wang, Yi-Wen,Lee, Gene-Hsiang,Lai, Chung K.
, p. 7729 - 7738 (2015/09/07)
Four new series of salicylaldazines 1 and salicylaldimines 2-4 were prepared, characterized and their mesomorphic properties were studied. The structures of all compounds were identified and confirmed by spectroscopic techniques such as 1H, 13C NMR, MS and elemental analysis. Three single crystallographic structures of compounds 1a (n=3, 6) and 2 (n=3) were determined by X-ray analysis in order to correlate the molecular structures with the formation of mesophases. Crystallographic data indicated that the better mesomorphic properties might be controlled by CH-π, π-π or/and H-bonds in such system. Except for crystalline compounds 4, all other compounds 1-3 showed mesomorphic behavior of nematic, smectic A or/and smectic C phases, which were characterized by differential scanning calorimetry, optical polarizing microscope and X-ray diffraction experiments. All compounds 1-4 showed yellow-green photoluminescence in THF occurred at 519-521 nm.
SYNTHESIS AND MESOMORPHIC PROPERTIES OF THREE HOMOLOGOUS SERIES OF 4,4 prime -DIALKOXY- alpha , alpha prime -DIMETHYLBENZALAZINES.
Marcos,Melendez,Serrano
, p. 157 - 172 (2007/10/02)
Three homologous series of alpha , alpha prime -dimethylbenzalazines have been synthesized: 4,4 prime -dialkoxy- alpha , alpha prime -dimethylbenzalazines, 4,4 prime -dialkoxy-2,2 prime -dihydroxy- alpha , alpha prime -dimethylbenzalazines, and 4,4 prime -dialkoxy-2-hydroxy- alpha , alpha prime -dimethylbenzalazines. The influence of molecular structure on the mesomorphic properties was studied. Mesomorphic properties and phase transitions were determined using a polarizing hot-stage microscope and a differential scanning calorimeter. The introduction of one or two hydroxyl groups in position 2- or 2-and 2 prime -of the aromatic rings (4,4 prime -dialkoxy-2-hydroxy- alpha , alpha prime -dimethylbenzalazines and 4,4 prime -dialkoxy-2,2 prime -dihydroxy- alpha , alpha prime -dimethylbenzalazines respectively) gives molecules with an excellent mesogenic quality, and all the prepared compounds of these series exhibit mesomorphism. Compounds of the series with two hydroxyl groups exhibit smectic polymorphism which is not so in the case of the compounds of the other series. The melting temperatures are systematically lower for the 4,4 prime -dialkoxy-2-hydroxy- alpha , alpha prime -dimethylbenzalazines than for the other two series.
