Synthesis, Crystal Structure and Luminescence Properties of a Cadmium(Ⅱ) Complex Based on 2-Hydroxy-6-methylisonicotinic Acid

A new cadmium（Ⅱ） complex[Cd（Hminic）（IP）]n（1,Hminic = 2-hydroxy-6-methylisonicotinic acid,IP = imidazo[4,5-f]-l,10-phenanthroline）,has been synthesized by the reaction of a Hminic and auxiliary N-containing ligands with Cd（Ⅱ） ion under hydrothermal conditions.The complex was studied by elemental analysis,IR spectroscopy and X-ray crystallography.It is formulated as C（20）H（13）CdN5O3,crystallizes in monoclinic system,space group C2/c with α=9.6764（8）,b = 26.767（2）,c = 14.1332（11） A and β= 97.4510（10）°.V= 3629.7（5） A^3,Z = 8,Mr=483.75,Dc = 1.770 g/cm^3,F（000） = 1484 and μ= 1.237 mm^（-1）.The final refinement gave R = 0.0309 and wR = 0.0703 for 4151 reflections with I 〉2σ（I）.In the structure of 1,two Cd（Ⅱ） atoms are joined by a pair of μ2-hydroxyl oxygen atoms giving rise to a dinuclear Cd（Ⅱ） unit which is bridged by Hminic linkers to form a 1D ladder-like polymer chain.The chelating ligand IP coordinated to the Cd（Ⅱ） atom,and alternately attached to both sides of the ladder-like polymer chain.Adjacent chains are further bound together by strong intermolecular hydrogen bonds and face-to-face π…πinteractions,resulting in the formation of a 3D supramolecular architecture.Furthermore,the thermal stability and luminescent properties of this complex and the free ligands have been investigated.

Supramolecular complex formation of β-cyclodextrin polymer with substituted salicylic acid or 3-hydroxy-2-naphthoic acid and their electrorheological behaviors

According to the chemical design, electrorheological properties of supramolecular complex from b-cyclodextrin polymer (b -CDP) were discussed. Six supramolecular complexes of -cyclodextrin polymer with substituted salicylic acid and 3-hydroxy-2-naphthoic acid were syn-thesized by the solid-phase self-assembly method, and their component and structure were characterized by NMR, FT-IR, UV-vis and the fluorescence analysis. Then the electrorheological properties of their suspensions in silicone oil were investigated under DC electric fields. It was found that the yield stresses of these supramolecular complex ER fluids were 7.3—9.8 kPa at 4 kV/mm in DC electric field, which were enhanced by 34%—72% compared with that of pure b-CDP. Among them, that of b-CDP/3-hydroxy-2-naphthoic acid ER fluid was the highest. It was also found that the ER effect of supramolecular complexes can be controlled by changing dif-ferent guests. When the substituted group is at phenyl ring, ER behavior can be slightly adjusted by the different substituted groups, their number as well as their position at phenyl ring. This can be proved by the measurement of dielectric properties.

4-(Succinimido)-1-butane sulfonic acid as a Bronsted acid catalyst for synthesis of pyrano[4,3-b]pyran derivatives under solvent-free conditions

4-（Succinimido）-1-butane sulfonic acid as an efficient and reusable Bronsted acid catalyzed the synthesis of pyrano[4,3-b]pyran derivatives under solvent-free conditions.The catalyst can be prepared by mixing succinimide and 1,4-butanesultone that is more simple and safer than the preparation of succinimide sulfonic acid.This method has the advantages of high yield,clean reaction,simple methodology and short reaction time.The catalyst could be recycled without significant loss of activity.