Honghong Chang

I2-Catalyzed C–O Bond Formation and Dehydrogenation: Facile Synthesis of Oxazolines and Oxazoles Controlled by Bases

A general method for the synthesis of oxazolines and oxazoles was developed through I2-catalyzed C-O bond formation and dehydrogenation with the same oxidant, TBHP. By simply tuning reaction bases, either oxazolines or oxazoles were selectively produced from β-acylamino ketones.

Pt NPs and DNAzyme functionalized polymer nanospheres as triple signal amplification strategy for highly sensitive electrochemical immunosensor of tumour marker

Highly sensitive determination of tumour markers is the key for early diagnosis of cancer. Herein, triple signal amplification strategy resulting from polymer nanospheres, Pt NPs, and DNAzyme was proposed in the developed electrochemical immunosensor. First, electroactive polymer nanospheres were synthesized by infinite coordination polymerization of ferrocenedicarboxylic acid, which could generate strong electrochemical signals due to plentiful ferrocene molecules. Further, the polymer nanospheres were functionalized by Pt NPs and DNAzyme (hemin/G-quadruplex) with the ability of catalyzing H2O2, which contributes to enhance the electrochemical signals. The prepared conjugations were characterized by transmission electron microscope (TEM) and energy dispersive X-ray spectroscopy (EDX). And the process of preparation was monitored by zeta potential. Based on the sandwich-type immunoassay, the electrochemical immunosensor was constructed employing the conjugations as signal tags. Under optimal conditions, the DPV peak increased with the increasing of alpha fetal protein (AFP) concentration, and the linear range was from 0.1pgmL(-1) to 100ngmL(-1) with low detection limit of 0.086pgmL(-1). Meanwhile, the designed immunosensor exhibited excellent selectivity and anti-interference property, good reproducibility and stability. More importantly, there were no significant differences in analyzing real clinical samples between designed immunosensor and commercial ELISA.

Iodine-catalysed sp3 C–H sulfonylation to form β-dicarbonyl sulfones with sodium sulfinates

An efficient and easily handled method for β-dicarbonyl sulfones with sodium sulfinates as the sulfonyl source was developed. This transformation was involved in the iodine-catalysed sp3 C–H sulfonylation of β-dicarbonyl compounds.

Hypoiodite-catalysed oxidative cyclisation of Michael adducts of chalcones with 1,3-dicarbonyl compounds: a facile and versatile approach to substituted furans and cyclopropanes

Through hypoiodite catalysis, oxidative cyclisation of Michael adducts of chalcones with 1,3-dicarbonyl compounds for divergent synthesis of either furans or cyclopropanes is developed. The selective synthesis of major products is achieved depending on the use of different reaction conditions or substrates.

I2-mediated sulfonylation and Na2SO3-mediated deacylation: a general protocol for the synthesis of β-keto sulfones and β-dicarbonyl sulfones

A general method for constructing both β-keto sulfones and β-dicarbonyl sulfones has been developed. β-Dicarbonyl sulfones were formed by iodine mediated α-sulfonylation of β-dicarbonyl compounds, and β-keto sulfones were prepared from β-dicarbonyl compounds by iodine mediated sulfonylation and sodium sulfinate mediated C–C bond cleavage in a one-pot procedure.

Highly photosensitive colorimetric immunoassay for tumor marker detection based on Cu2+ doped Ag-AgI nanocomposite

Visual detection of tumor markers with accuracy and selectivity exhibits significant advantages for cancer early diagnosis due to its low-cost and simple analytical instruments. Herein, a highly photosensitive colorimetric immunoassay for carcino embryonie antigen (CEA, as a model) detection based on Cu2+ doped Ag-AgI nanocomposite was constructed. First, Cu2+ doped Ag-AgI nanocomposite (Cu2+/Ag-AgI) owned the ability of oxidization of TMB was synthesized by impregnation method, which was characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectroscopy (XPS). Second, based on sandwich-type immunoassay, the immunocomplex was built on the surface of magnetic bead by utilizing Cu2+/Ag-AgI as labels. The blue color of TMBox was obtained under visible irradiation and ultraviolet spectrum scanning was carried out in ABS buffer solution. Under optimal conditions, the absorbance values increased with the increasing of CEA concentrations in sample with the linearity range of 1.0pgmL-1-5.0ngmL-1. The detection limit was 0.13pgmL-1. More importantly, the developed colorimetric immunoassay exhibited good selectivity, repeatability, stability and possible applications in the real serum sample analysis.

A simple and fast chromogenic reaction based on Ag3PO4/Ag nanocomposite for tumor marker detection

Colorimetric assay is a powerful tool for detection of tumor markers with the outstanding advantages of visualization and simple analytical instruments. Herein, a simple and fast chromogenic reaction was developed based on Ag3PO4/Ag nanocomposite synthesized by one-step chemical bath method. And the Ag3PO4/Ag nanocomposite owned the ability of oxidizing of TMB under the acidic condition due to the hydrolytic action. The nanocomposite was characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Then, the colorimetric immunoassay was constructed by utilizing Ag3PO4/Ag nanocomposite as molecular labels for carcino embryonie antigen (CEA, UniProt accession number: P06731) detection. The blue color with gradient change was observed with the increasing of CEA concentrations. Under optimal conditions, the variation between absorbance values and CEA levels was linear in the range of 0.2ngmL-1 ~ 2.5ngmL-1 with the detection limit of 0.03ngmL-1. More importantly, the developed colorimetric immunoassay exhibited good selectivity, repeatability, stability and potential application in the real serum sample detection.

Ligand- and copper-free Sonogashira and Heck couplings of (Het)aryl chlorides and bromides catalyzed by palladium nanoparticles supported on in situ generated Al(OH)3

The ligand- and copper-free Sonogashira reaction of (Het)aryl halides (Br and Cl) with various terminal alkynes and the Heck coupling of (Het)aryl halides (Br and Cl) with a series of olefins, catalyzed by palladium nanoparticles supported on newly generated Al(OH)3, were developed. The catalyst can be readily recovered and reused 6 times without significant loss of activity and palladium leaching.

AlCl3-Catalyzed Intramolecular Cyclization of N-Arylpropynamides with N-Sulfanylsuccinimides: Divergent Synthesis of 3-Sulfenyl Quinolin-2-ones and Azaspiro[4,5]trienones

Switchable ortho/ipso-cyclization of N-arylpropynamides induced with N-sulfanylsuccinimides as general sulfur reagents is reported. In the presence of MeOH, para-fluoro N-arylpropynamides exclusively undergo the ipso-cyclization to give 3-sulfenyl azaspiro[4,5]trienones. Two kinds of bioactive heterocycles, benzothieno-[3,2-b]quinoline and -[2,3-c]quinolone, have been directly and efficiently prepared from the corresponding sulfenylated products.

The preparation of coal pitch slurry with coking wastewater.

This study explored the feasibility of using coking wastewater and coal pitch powder to make coal pitch wastewater slurry. The medium temperature coal tar pitch powder was prepared by freezing and pulverizing coal tar pitch. The dispersant, JL-C01 medium-breaking emulsifier, had a large adsorption value on the coal pitch surface. At the same time, the Zeta potential on the coal pitch having added dispersant had a big increase. On the basics of that, putting some dispersants and wastewater into the powder under high speed stirring, the coal pitch wastewater slurry was obtained. The slurryability, rheological behavior, and static stability of coal pitch wastewater slurry were investigated at different dispersant dosages and slurry concentrations. The results showed that the apparent viscosity decreased with increasing the shearing rate. The rheological behavior of the slurry exhibited pseudo-plasticity. The biggest slurryability could be up to 70%. When the slurry concentration was 70%, the slurry could be kept for 28 d. At last, considering the test methods for quality of coal water mixture, the combustion analysis of the slurry was carried out and many indexes accorded with the national standard. The low heat value, the ash content, and the volatile matter met the coal water slurry first grade standard, and the sulfur content met the second grade standard.