A Novel Approach to the Stereoselective Synthesis of (E)-1-(1-Alkenyl)Benzotriazoles

The Horner-Wadsworth-Emmons olefination of diethyl-(1-benzotri-azolmethyl)phosphonate by means of aldehydes was found to be a convenient method for the stereoselective preparation of (E)-1-(1-Alkenyl)benzotriazoles.     

Synthesis of Novel Naphthoquinone Fused 1, 3-Dithioles

2, 3-Dichloro-1, 4-naphthoquinone 3 reacts with 1, 1 -dithiolates 2, prepared from the reaction of CH-acids and carbon disulfide, to give 2-methylidene-4, 10-dioxonaphtho [2, 3-d]-1, 3-dithioles 4. The similar reaction of 3 and dithiocarbamates 6 affords 2-imino-4, 10-dioxonaphtho [2, 3-d] dithioles 7.     

Fabrication and luminescent properties of Eu(BMPPA)3BPy complex and its functionalized silica nanocomposites

Luminescent silica nanocomposites functionalized with a Eu-complex have been prepared and characterized.The europium complex is composed of 2,2'-bipyridyl(BPy) and 2-(4-bromomethyI)-phenylpropionic acid(BMPPA),which contains highly active benzyl bromide substituents and can covalently bind with poly(4-vinylpyridine)(P4VP)-modified silica nanoparticles(nanoSiO_2P4VP) to form nanoSiO_2P4VPEuBPy composites.Microscopic images revealed that the nanoSiO_2P4VPEuBPy composites easily formed aggregates,due to an inter-particle binding caused by the benzyl bromide among the composites.The as-prepared nanocomposites showed the typical emissions of Eu(III) ions at the wavelengths from 580 nm to 750 nm designated to the ~5D_0→~7F_n transitions.Time-resolved fluorescence decay measurements revealed that the emission lifetime was approximately 0.204 ms and 0.576 ms for the nanoSiO_2EuBPy composites,a little shorter than that in the Eu(BMPPA)_3BPy complex.     

Nucleophilic imidoesterification of dicarbonyl compounds with cyanatobenzenes through C-C bond formation

Under neat conditions,an efficient method for synthesis of imidoesters has been developed using cyanatobenzenes and dicarbonyl compounds.Nucleophilic addition spontaneously occurred between the two kinds of materials at room temperature with yields of up to 90%.A mechanism directed towards to the imidoester formation has been proposed.     

Study on viscoelastic properties of epoxidized trans-1,4-polyisoprene by rubber process analyzer

Two kinds of epoxidized trans-1,4-polyisoprene (ETPI) were prepared by surface selective epoxidation which products named as SETPI and solution random epoxidation which product named as RETPI, respectively. The viscoelastic behavior of unmodified trans-1,4-polyisoprene (TPI) and ETPI, both RETPI and SETPI, was studied with the use of a rubber process analyzer (RPA). The strain sweep, frequency sweep, temperature sweep and stress sweep indicated that the SETPI could be seen as a blend of the pure ETPI and TPI. The rheological behavior of TPI and ETPI was recorded by two kinds of shear rate. An obvious effect of epoxidation on the movement behavior of the melt of RETPI was observed. However, the effect of epoxy content of SETPI on ln??* is weak. The complex viscosity at various frequencies of SETPI is higher than that of RETPI.     

Synthesis of tetrazole containing 1,2,3-thiadiazole derivatives via U-4CR and their anti-TMV activity

A series of novel tetrazole containing 1,2,3-thiadiazole derivatives were designed and synthesized via Ugi reaction. Their structures were confirmed by melting points, IR, 1H NMR, and HRMS (ESI). Preliminary bioassay indicated that most target compounds exhibited very good direct anti-TMV activity at 100 μg/mL, which was equal to or higher than that of ribavirin. Among them, compounds 4b, 4c and 4i also showed equivalent protection effect to ribavirin in vivo at 100 μg/mL.