A New Schiff Base Derivatives Designed to Bind Metal Ion (Cu, Co): Thermodynamics and Biological Activity Studies

Schiff base synthesis is usually acid catalyzed and it usually requires refluxing the mixture of aldehydes and amine in ethanolic solution. Synthesis and characterization of Schiff base ligands derived from substituted amine and salicylaldehyde and their complexes (Cu2+, Co2+) are reported. The ligands and ligand-complexes were characterized by melting point, FTIR, CHN-elemental analysis and UV-Visible analysis. The UV-Visible and elemental analysis of complexes established (1:2) mole ratio (M:L). The stability constant and thermodynamic parameters (K, ΔG, ΔH, ΔS) were determined at different temperature (30 - 40)°C which established that the metal-complexes were very stable. The review describes the promising biological activities of Schiff base and their metal complexes.

COMPLEXES OF RARE EARTH NITRATE WITH SCHIFF BASE DERIVED FROM VANILLIN AND P-TOLUIDINE

In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-Eu except Pm,L=Schiff base ligand) have been prepared and characterized.

Design,synthesis and evaluation of novel cis-p-menthane type Schiff base compounds as effective herbicides

p-Menthane type monoterpene derivatives were identified as bio-based compounds with high herbicidal activities. In order to search novel p-menthane type monoterpene derivatives in good performance, a series of novel cis-p-menthane type Schiff base derivatives were designed and synthesized. All target products were easily available novel compounds and characterized by FT-IR,^1H NMR,^13 C NMR and ESI＋-MS. Their pre-emergence herbicidal activities against annual ryegrass were evaluated. The bioassays indicated that most of the target compounds displayed excellent herbicidal activities in pre-emergence treatment.

Enantioselective recognition based on aggregation-induced emission

Chirality is one of the most important features of the nature.The recognition of enantiomers plays significant roles in the field of life science,pharmaceutical analysis and food chemistry.Among various recognition methods,fluorescence spectrometry has attracted much attention of researchers thanks to its high sensitivity and easy operation.Compared with traditional fluorescent probes,chiral molecules with aggregation-induced emission(AIE)have drawn increasing interests due to their huge potential in high-efficiency chemo/biosensors and solid emitters.Chiral AIE luminogens(AIEgens)can not only discriminate two enantiomers with excellent enantioselectivity,but also show general applicability for many chiral analytes,such as chiral acids,amino acids,amines,alcohols.In this review,we mainly summarized the recent development of chiral probes with AIE properties,including chiral tetraphenylethylene(TPE)derivatives,α-cyanostilbene derivatives,Schiff base derivatives and other AIEgens.Their synthetic routes,recognition capabilities and possible working mechanisms were well discussed.It is envisioned that the present review can give some significant guidance for design and synthesis of chiral AIEgens with good enantioselectivity and inspire more readers to join the research of chiral AIE.

Synthesis and Crystal Structure of a Novel Bis(chlorido)-bridged One-dimensional Chain-like Copper(Ⅱ) Polymer

A copper（Ⅱ） complex [LCu2Cl4]n was synthesized by a new bis-Schiff base ligand containing quinoline unit, 1,4-bis[2-（4-fluorophenyl）iminomethyl-8-quinolinoxy]butane（L）. X-ray crystal structure shows that it is a binuclear complex, and the crystal belongs to the triclinic system, space group P1, with a = 9.387（2）, b = 9.968（2）, c = 10.291（2） ？, α = 87.532（3）, β = 63.762（2）, γ = 86.628（3）o, V = 862.1（3） ？^3, Z = 1, Dc = 1.640 Mg/m^3, F（000） = 428, R = 0.0416 and wR = 0.1141. Each Cu（Ⅱ） metal ion coordinates with a quinoline N atom, an imine N atom, an ether oxygen atom and three chlorides, forming a distorted six-coordinated octahedronal structure. Each copper（Ⅱ） complexation unit links with one of the adjacent ligand copper complexation units through the chlorido bridging groups, thus generating an infinite one-dimensional chain structure. Such 1D chains further construct a 2D network structure by π-π stacking interactions.