6，6‘—二甲氧基—4，5，4’,5‘—二亚甲基二氧基—2，2’—联苯二甲酸二甲酯及其衍生物的合成研究

以没食子酸为原料经酯化、醚化、区域选择性硝化、还原、Sanmeyer及分子间Ulmann耦合等反应以较高产率合成6,6‘-二甲氧基-4,5,4‘,5‘-二亚甲基二氧基-2,2‘-联苯二甲酸二甲酯（β-联苯双酸,β-DDB）,并对其进行衍生化,得到5个β-DDB的衍生物,用IR,^1H NMR和MS等鉴定了其结构,使用手性柱对β-DDB进行拆分得到了两个对映异体,利用圆二色谱确定了它们的立体构型。     

4,4′-Dibromo-2,2′,3,3′,5,5′,6,6′-octafluorobiphenyl

The mol­ecule of the title compound, C₁₂Br₂F₈, shows approximate D₂ symmetry. The dihedral angle formed by the two rings is 60.2 (1)°.     

A 2,2',6,6'-tetraphosphinobiphenyl

The first example of a 2,2',6,6'-tetraphosphinobiphenyl was prepared and used as a ligand in a dinuclear palladium(II) complex. The close proximity of the two complex fragments induces a coupling pathway allowing the allosteric communication between the two palladium complex fragments.     

The synthesis and liquid crystal properties of certain 1-(4'-n-alkoxy-2,2',3,3',5,5',6,6'-octafluorobiphenyl-4-yl)- 2-(trans-4-n-pentylcyclohexyl)-ethanes and -ethenes

The synthesis and liquid crystal properties of eight members of the homologous series of 1-(4'-n-alkoxy-2,2',3,3',5,5',6,6'-octafluorobiphenyl-4-yl)-2-(trans-4-n-pentylcyclohexyl)-ethanes and eight members of the corresponding -ethanes, which have the E-configuration, are reported. These compounds are nematic, the ethenes having a considerably mesophase higher thermal stability than the analogous ethanes.     

New approach to the synthesis of 2,2':5',2'-terthiophene-5,5'-and 2,2':5',2':5',2'-quaterthiophene-5,5'-dicarboxylic acids

Chemistry of Heterocyclic Compounds - The reaction of bromosuccinimide with esters of 3-substituted 2,2'-bithiophene-5-carboxylic acids was used to obtain their 5'-bromo derivatives, which...