3,4′,5-三甲氧基-1,2-二苯乙烯合成、晶体结构与量子化学研究

Synthesis,Crystal Structure and Quantum Chemistry Studies of 3,4',5-Trimethoxystilbene

利用Wittig-Horner反应制备了抗癌保健药物白藜芦醇的前体化合物3,4′,5-三甲氧基-1,2-二苯乙烯,单晶结构解析结果表明,该晶体属于三斜晶系,空间群P1,晶胞参数:a=0.9960(12)nm,b=1.0040(12)nm,c=1.6194(19)nm,α=90.702(2)°,β=105.515(2)°,γ=111.815(2)°,V=1.6194(3)nm3,Dc=1.249Mg/m3,结构基元分子数Z=2.对晶体结构的结构基元进行了量子化学研究,计算结果表明,3,4′,5-三甲氧基-1,2-二苯乙烯晶体结构基元与组成结构基元分子两种不同构象能量和的差值为ΔEBSSE=5.51kJ/mol.因此,晶体结构基元中两种构象之间存在π-π堆积相互作用.

3,4＇, 5-Trimethoxystilbene was synthesized via Wittig-Horner reaction with different solvents. It belongs to triclinic system with crystal space group P1. Hydrogen bond interaction existed between different structure units in a crystal cell. There were two different conformations in the crystal structure unit. The results, obtained by quantum chemistry method with DFT/B3LYP/6-31 G, 6-311G （5 D, 7F） sets, show that the total energy of the two separated conformations was higher than that of the two conformations in one structure unit, AEBssE = 5. 51 kJ/mol. Otherwise the optimization of all the molecular shows that when the crystal formed, the plan-structure of different conformations was twisted, which indicate that there was a π-π effect between the two conformations.