New π-conjugated cyanostilbene derivatives:Synthesis,characterization and aggregation-induced emission

Two novel π-conjugated cyanostilbene derivatives,FLU-CNPH and TPE-CNPH,were designed and synthesized by introducing the strong electron donor 1,4-dihydropyrro[3,2-b]indole and AIE electron donor tetraphenylethylene(TPE)to the(3',5'-bis(trifluoromethyl)-biphenyl-4-yl)-acetonitrile,respectively.Both of them were fully characterized and their AIE behaviors were investigated using fluorescence spectroscopy and FE-SEM images.Their optimized structures and frontier molecular orbitals were calculated with the DFT by using Materials Studio 7.0 software to study the relationship between the structure and properties.     

New mesogenic Schiff base esters comprising benzothiazole moiety： Synthesis and mesomorphic properties

A homologous series of Schiff base esters,6-methoxy-2-(2-hydroxy-4-alkanoyloxybenzylidenamino)benzothiazoles,comprising a benzothiazole moiety as the core was synthesized.All the members of this series exhibited an enantiotropic nematic phase. The azomethine linkage along with the lateral hydroxyl and terminal methoxyl groups were found to exert an effect on the mesomorphic properties.     

Synthesis and characterization of novel β-amino acid derivatives

In the work discussed in this paper, novel β-amino acid derivatives were prepared by Michael addition between 3-substituted-2-propenic acid and hydrazine hydrate. The optimum reaction conditions were determined by analyzing the effects of the ratio of the starting materials, temperature, and reaction time. The conclusions were: reaction temperature 80 °C, reaction time 8 h, n (3-substituted-2-propenic acid)/n (hydrazine hydrate) = 1:15. Products were characterized by measurement of melting point, elemental analysis, and IR and ¹H NMR spectroscopy.     

Synthesis and characterization of water-swellableα,β-polyasparthydrazide derivatives

, -polyasparthydrazide (PAHy) was crosslinked by glutaraldehyde to form water-swellable materials possessing a three-dimensional molecular network. Different crosslinking degrees were prepared varying glutaraldehyde/PAHy ratio and samples containing 5-fluorouracil were obtained by incorporating the drug into the polymer networks during the crosslinking reaction. All samples were characterized by swelling tests, thermal, x-ray and SEM analysis. Their microstructure was observed through scanning electron microscopy. Furthermore, for samples containing the anticancer drug,in vitro release studies were performed in pH 7.4 buffer solution.     

Synthesis and characterization of water-swellableα,β-polyasparthydrazide derivatives

The synthesis of a new crosslinked polymer by reaction of , -polyasparthydrazide and glutaraldehyde is reported. Different crosslinking degrees were obtained by varying the ratio between the aldehyde and the starting polymer. The crosslinked polymer was characterized by water swelling tests and thermal analysis. In particular, the crosslinking density and its effects on the glass transition temperature of the material were studied. Finally, the microstructure of the obtained polymer was observed using scanning electron microscopy.     

Synthesis and mesomorphic properties of trifluorobenzoate liquid crystal

Four series of trifluorobenzoate liquid crystals have been synthesized. Their phase transition temperatures have been also measured by texture observation in a polarizing microscope and confirmed by DSC. The influence of the lateral fluoro-substitution and triple bond has been also discussed.     

Synthesis,physicochemical characterization,and TD–DFT calculations of monothiocarbohydrazone derivatives

Structural Chemistry - Derivatives of thiocarbohydrazone studied so far have shown great biological activity such as antioxidant, antimicrobial, and anticancer. Most of these compounds are...     

Synthesis and mesomorphic properties of new azine-type liquid crystals

A series of symmetrical azine-type liquid crystals were synthesized. The characteristic of these liquid crystals is that they had high clearing point ( ～320 ℃) and broad thermal range of nematic phase ( ～154 ℃). It was also found that the end groups of the liquid crystals had effect on the mesomorphic properties.     

Synthesis and mesomorphic properties of 2-(4′-alkoxybiphenyl-4-yl)-1H-benzimidazole derivatives

Three series of 2-(4′-alkoxybiphenyl-4-yl)-1H-benzimidazole derivatives (nM-x), which possessed 5-nitrobenzimidazole (nM-N series), benzimidazole (nM-H series) or 5-methylbenzimidazole (nM-M series) units at the end of the molecule, were synthesised and characterised by infrared, ¹H- and ¹³C-nuclear magnetic resonance spectra, electrospray ionisation-mass spectrometry and elemental analysis. Their phase transition behaviour was investigated by differential scanning calorimetry, polarising optical microscopy and X-ray diffraction. All the compounds exhibited enantiotropic smectic mesophases with wide temperature domains for a carbon number in the alkoxy chain from 6 to 16, where the mesophase ranges were 14–91°C and 17–99°C during heating and cooling processes for the nM-N compounds, 7–25°C and 8–49°C for the nM-H compounds and 48–81°C and 52–85°C for the nM-M compounds, respectively. The effect of the length of alkoxy chain on mesomorphic properties was discussed. The nM-N and nM-M exhibited a much wider mesophase range whether during heating or cooling process than the corresponding nM-H series, especially for the longer terminal chain (n > 8), which indicated that the substituent in the benzimidazole moiety was helpful in increasing the mesophase stability.     

Synthesis and characterization of adducts of p-azidostyrene derivatives to fullerene C_(60)

Fullerene C60 reacted with p-azidostyrene derivatives in refluxing chlorobenzene,yielding monoadducts 2a and 2d as well as diadduct 2c with aziridine structure at 6/6-ring junctions.Experimental results showed that the addition of the second azide to the monoadduct was regioselective.The diadduct,of Cs symmetry in C60 moiety,was unstable by opening to be 1,6-imido[10]annulene structure.     

Synthesis and characterization of magnetic nanoparticles

Magnetic nanoparticles with average diameter in the range of 6.4-8.3 nni have been synthesized by a chemical co-precipitation of Fe(Ⅱ)and Fe(Ⅲ)salts in 1.5 M NH4OH solution.The size of the magnetic particles is dependent on both temperature and the ionic strength of the iron ion solutions.The magnetic particles formed at higher temperature or lower ionic strength were slightly larger than those formed at lower temperature or higher ionic strength respectively.In spite of the different reaction conditions,all the resultant nanoparticles are nearly spherical and have a similar crystalline structure.At 300 K,such prepared nanoparticles are superparam-agnetic.The saturation magnetizations for 7.8 and 6.4 nm particles are 71 and 63 emu/g respectively,which are only ~ 20-30% less than the saturation magnetization(90 emu/g)of bulk Fe3O4 Our results indicated that a control of the reaction conditions could be used to tailor the size of magnetic nanoparticles in free precipitation.     

Synthesis and electroluminescent properties of naphthalimide derivatives

Naphthalimide derivatives, N-ethyl-4-acetylamino-l ,8-naphthalimide (EAAN) and polymer with N-propyl-4-acetylamino-l,8-naphthalimide (PAAN) side-chain (P-PAAN) were successfully synthesized. Electroluminescent devices of ITO/PVK(120nm)/EAAN(50nm)/Al(150nm) (Ⅰ) and ITO/PVK P-PAAN( 10:1) (50nm)/Al(150nm) (Ⅱ) constructed with EAAN and P-PAAN as the emitting layer were investigated, whereas the single-layer devices of ITO/EAAN or P-PAAN(50nm)/Al(l50nm) (Ⅲ) were not observed to have any e-mission light. The emission results revealed that the exciton recombination formed by positive and negative charge carriers injected from electrodes of devices Ⅰ and Ⅱ was much more balanced than that of devices Ⅲ, which implied that naphthalimide derivatives are a new type of electron-transporting materials with high performance. The electron-transporting properties of naphthalimide derivatives were also elucidated by investigation of the electroluminescent behaviors from both devices of ITO/PPV (80nm)/Al and ITO/P     

Synthesis and structure characterization of novel calix[4]（aza）crown derivatives

Three novel calix[4](aza)crown deravatives have been synthesized,including a new [2]pseudorotaxane in which calix[4]- azacrown behaves as a stopper,a novel‘tren’type calix[4]azacrown and a novel‘spiro’type calix[4]azacrown containing morpholine unit.The structures of these compounds have been confirmed by NMR and MS.     

Synthesis of γ-benzyltert-butoxycarbonyl-L-alanyl-D-glutamate and its derivatives

A convenient method of obtaining Boc-L-Ala-D-iGln-OBzl and its amide analogs by condensing the N-hydroxysuccinimidyl ester of Boc-L-Ala with the -benzyl ester ofD-Glu in the presence of NaHCO₃, followed by amidation of the resulting Boc-L-Ala-D-Glu--OBzl, is proposed. The use of l-adamantylamine and octadecylamine as amino components has enabled the corresponding -adamantylamide and octadecylamide of the dipeptide to be obtained.Simferopol' State University, 4 Yaltinskaya ul., Simferopol', Crimea, Ukraine 333036. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 101–103, January–February, 1998.     

Synthesis and mesomorphic properities of some ferroelectric liquid crystals of lactate

A semiperfluorinated chain has been introduced into three series of lactate-based molecules,and their mesomorphic properities have been studied by DSC and optical polarized microscope.An abnormal phenomenon has been found that the introduction of a triple bond in the core of the molecule,which lengthened the molecule,gave rise to a decrease in the thermal stability of chiral smectic C phase and smectic A phase.2,3-Difluoro substituents of the phenylenic structure hinder the formation of the chiral smectic C phase because of the steric effect.     

Synthesis and characterization of chiral copper(ii) coordination polymers with 4,4´-bipyridine and lactic acid derivatives

Russian Chemical Bulletin - Chiral 2D and 3D metal-organic coordination polymers [Cu2(bpy)2(Hdml)2(HCOO)]-(HCOO)·2H2O (1) and [Cu(bpy)(Hphl)(HCOO)]·H2O (2) were synthesized by heating a...