3-烷氧基-6-（4-甲氧羰基苯基）哒嗪的合成及介晶性研究

3，6-二氯哒嗪和醇在相转移催化剂(C_4H_9)_4NBr和浓碱作用下，合成3-氯- 6-烷氧基哒嗪，在三苯基膦钯的催化下，用3-氯-6-烷氧基哒嗪与对甲氧羰基苯基 硼酸偶联，并以较好产率合成了八种中心桥连基为哒嗪环，含有苯环、酯基、不同 长度烷氧基的哒嗪衍生物，并通过差示扫描量热法（DSC）对其介晶性进行了表征 ，同时发现其中七种都具有介晶性。研究表明，末端链长度对相变温度和清亮点温 度均有影响。

Synthesis and Liquid Crystal Behavior of 3-Alkoxy-6-(4- methoxycarbonylphenyl) pyridazines

The reaction of 3,6-dichloropyridazine with alcohol under phase transfer catalyst gives 3-chloro-6-alkoxypyidazine. Eight new 3-alkoxy-6-(4-methoxycarbonylphenyl)pyridazines which contain a benzene ring, an ester group, an alkoxyl group with different length were synthesized in high yields through the cross-coupling reaction of 3-halo-6-alkoxypyridazines with p-methoxycarbonylphenylboronic acid in the presence of palladium catalyst. Their mesomorphism was studied through differential scanning calorimetry (DSC), and seven compounds were found to have mesomorphism.The length of the terminal chain can affect the transition and clearing point temperatures of the complexes, but has little influence on the temperature range of mesomorphous phases.