•A Mn(III)Cl(α,α′-n-OC5H11)8Pc can be used as a catalyst for highly efficient carbon-chloride bond cleavage.•The increased catalytic efficiency is related to the enantiomeric carbon-chloride σ-bond of HCHs.•Both experimental investigation and theoretical calculation are carried out in the current study.A lipophilic and electron-rich metallophthalocyanine Mn(III)Cl(α,α′-n-OC5H11)8Pc has been synthesized and characterized. A series of electrochemical experiments demonstrate that the Mn(III)Cl(α,α′-n-OC5H11)8Pc complex can be used as a catalyst for highly efficient carbon-chloride bond cleavage of environmental toxic hexachlorocyclohexanes (HCHs) through electrochemical catalysis, and that the increased catalytic efficiency is related to the enantiomeric carbon-chloride σ-bond of HCHs.

•The first example of the complete dechlorination of DDT through molecular electrochemical catalysis.•Highly efficient CCl bond cleavage is achieved and an unprecedented CC bond cleavage reaction also occurs.•The electronic structure and properties of the molecular catalyst is characterized by various techniques.•GC–MS has been used to analyze the degradation products and the reaction mechanism is fully described.The electrocatalytic properties of a Co(II)octaalkoxyphthalocyanine complex (Co(II)Pc) with eight strongly electron-donating substituents provide the first example of the complete dechlorination of DDT through molecular electrocatalysis, rather than the use of metal electrodes which had been achieved previously. Interaction with a highly nucleophilic [Co(I)Pc]2− species results in rapid cleavage of the C(sp3)Cl, C(sp2)Cl and aromatic C(sp2)Cl bonds. Bis(p-chlorophenyl)methanone (BPCl2) is detected in high yield along with its full dechlorination product, diphenylmethanone (BP) and the conventional CCl bond cleavage products, due to an unprecedented CC bond cleavage reaction that is followed by the formation of a C−O bond. Theoretical calculations are used to analyze trends in the electronic structure of the Co(II)octaalkoxyphthalocyanine complex that account for the efficiency of the CCl bond cleavage reactions, and the reaction process and mechanism are analyzed in depth.Download high-res image (105KB)Download full-size image

•Seven low symmetric A2B type Co(III)triarylcorroles have been reported.•The electronic structure has been characterized by optical spectroscopy, electrochemistry, spectroelectrochemistry and TD-DFT calculations.•These Co(III)corroles are highly effective catalysts for unusual two steps modulation of hydrogen evolution reactions (HERs).Seven low symmetry A2B type Co(III)triarylcorroles with electron withdrawing meso-aryl substituents have been synthesized and characterized. A detailed analysis of the optical and redox properties has been carried out by comparing their optical spectroscopy, electrochemistry and spectroelectrochemistry to trends predicted in a series of DFT and TD-DFT calculations. The results demonstrate that Co(III)corroles are highly effective catalysts for hydrogen evolution reactions (HERs). Moreover, there is a marked enhancement in their homogenous catalytic ability when halogen atoms are introduced at the B position, which demonstrates that facile modifying the meso-aryl rings is a effective strategy for developing new HER catalysts. The electrochemical results demonstrate that an unusual two step modulation of HER reactions can be achieved by using singly and doubly electrochemical reduced cobalt triarylcorroles anions.

In this study, a facile dechlorination of lindane is achieved under mild electron reductive conditions with a series of Co(III)corroles used as electrocatalysts. Spectroscopic, electrochemical, and spectroelectrochemical measurements are used to determine the mechanism of the reaction. A GC–MS analysis of the dechlorination products indicates that the meso-aryl substituents of the cobalt(III)corroles have a significant influence on the dechlorination efficiency when a fixed potential is applied. Under reductive catalysis, the Co(III)corroles provide highly satisfactory dechlorination results, since lindane was ultimately converted to chlorobenzene.

•In this manuscript, meso-pentafluorophenylporphyrin with decreased electron density of macroheterocycle rings performed enhanced reductive electrocatalytic dechlorination of DDT up to 100% within 3 hours. Spectroscopy, electrochemistry, spectroelectrochemistry, and GC–MS measurements provide useful information about the relationship between the electronic structure and electrocatalyzed dechlorination efficiency of organochlorides.A rationally designed meso-tetrakis-(pentafluorophenyl)porphyrin iron(III) chloride [(TF5PP)Fe(III)Cl] was examined as electron reductive dechlorination of environmental harmful 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) in nonaqueous media. Due to the introduction of strong electron-withdrawing groups at meso-positions, (TF5PP)Fe(III)Cl exhibits 100% overall degradation efficiency of DDT by using the controlled-potential electrolysis. The time-dependent dechlorination products were analyzed by GC–MS, and the mechanism was studied by in-situ spectroelectrochemical measurements. This rationally designed model catalyst revealed higher degradation speed and efficiency that provide useful information for future rational molecular design towards highly efficient removal of environmental harmful organochloride catalyzed by metallo-porphyrins.

•A simple, rapid and label-free biosensor for detection of GM soybean was proposed.•The DNA biosensor was constructed without multiple modified or labeled procedures.•Wide linear range and low detection limit for CaMV 35S detection was obtained.•The proposed method has the merits of good selectivity, reproducibility and stability.•The DNA biosensor showed satisfactory results to discriminate GM soybean samples.We report a simple and label-free electrochemical impedimetric DNA biosensor for genetically modified (GM) soybean detection by recognizing the Cauliflower Mosaic Virus 35S (CaMV 35S). In the detection system, gold nanoparticles decorated multiwalled carbon nanotube-reduced graphene oxide nanoribbons were employed to anchor the probe single-stranded DNA. When the target DNA fixed on the modified electrode surface via hybridizing reaction, the impedimetric signal showed a growing tendency due to the formed double-stranded DNA restraining the electron transfer process. Under optimal conditions, the increased impedimetric signal of the proposed DNA biosensor was linear with the logarithm of the target DNA concentrations in the range of 1 × 10− 16 M–5 × 10− 10 M with a low detection limit of 3.3 × 10− 17 M. Moreover, the biosensor possessed excellent selectivity for discriminating complementary sequences from mismatched DNA as well as satisfactorily applied for practical detection of GM soybean samples.

•Solvent-controlled difluoromethylation of 2′-hydroxychalcones is developed.•The difluoromethyl ethers are obtained with 47–97% yields in p-xylene.•The difluorinated cyclic ethers are obtained with 21–75% yields in acetonitrile.•Difluorocarbene forms two chemical bonds between phenol O and carbonyl C.The solvent-controlled difluoromethylation of 2′-hydroxychalcones using the shelf-stable reagent difluoromethylene phosphabetaine for divergent synthesis of 2′-difluoromethoxychalcones and 2,2-difluoro-3-styryl-2,3-dihydrobenzofuran-3-ols is developed. When difluoromethylation was performed in p-xylene, 2′-difluoromethoxychalcones were the major product with 47–97% yields, while 2,2-difluoro-3-styryl-2,3-dihydrobenzofuran-3-ols were obtained in 21–75% yields using acetonitrile as solvent. A plausible reaction mechanism was proposed according to the experimental results.The solvent-controlled difluoromethylation of 2′-hydroxychalcones using the shelf-stable reagent difluoromethylene phosphabetaine for divergent synthesis of 2′-difluoromethoxychalcones and 2,2-difluoro-3-styryl-2,3-dihydrobenzofuran-3-ols is developed. When difluoromethylation was performed in p-xylene, 2′-difluoromethoxychalcones were the major product with 47–97% yields, while 2,2-difluoro-3-styryl-2,3-dihydrobenzofuran-3-ols were obtained in 21–75% yields using acetonitrile as solvent.

•Different deep eutectic solvents were applied for oxidative desulfurization.•Desulfurization efficiency can be greatly promoted by adding a few amount of DES.•The neutral DES ChCl/2PEG showed the best performance.•The oxidative products DBTO and DBTO2 were proved by GC–MS analysis.In this study, a new type of “green solvents” named deep eutectic solvents (DESs) has been synthesized by combining hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs). Choline chloride (ChCl) was chosen as typical HBA, and polyethylene glycol (PEG), 1,3-butyleneglycol (BG), ethylene glycol (EG), glycerol (Gl), propionate (Pr), malonic acid (MA) and urea (U) were chosen as HBDs. The extraction and catalytic oxidative desulfurization (ECODS) system was evaluated with phosphotungstic acid (HPW) as catalyst and 30 wt% H2O2 as oxidant. Among all the neutral, acid and basic DESs, choline chloride/2polyethylene glycol (ChCl/2PEG) showed the best performance and 99.1% of dibenzothiophene (DBT) could be eliminated from model oil at 50 °C within 3 h. Interestingly, the volume ratio of DES to model oil was just 1:10, which was much less than the amount of extractant in the literature. The gas chromatography–mass spectrometer (GC–MS) analysis demonstrated that DBT sulfoxide (DBTO) and sulfone (DBTO2) were the products of oxidation of DBT. The desulfurization efficiency of the five sulfides in ECODS system occured in the following order: DBT > 4-MDBT > 4,6-DMDBT > 3-MBT >BT.Different deep eutectic solvents combining choline chloride (ChCl) and hydrogen bond donor were synthesized and used as w new green solvent in the field of oxidative desulfurization. Dibenzothiophene (DBT) in model oil was removed completely in ChCl/2PEG with HPW as catalyst in the presence of H2O2 under mild conditions. The oxidation products consist of sulfoxide DBTO and sulfone DBTO2.

A lipophilic and electron-rich phthalocyanine (α,α′-n-OC5H11)8-H2Pc and its nickel(II) complex (α,α′-n-OC5H11)8-Ni(II)Pc have been synthesized and characterized. Detailed analyses of the electronic structure were carried out by spectroscopy, electrochemistry, spectroelectrochemistry, and TD-DFT calculations. A series of experiments demonstrate that the (α,α′-n-OC5H11)8-Ni(II)Pc complex can be used as a catalyst for highly efficient carbonyl reductions.

A lipophilic and electron-rich phthalocyanine (α,α′-n-OC5H11)8-H2Pc and its nickel(II) complex (α,α′-n-OC5H11)8-Ni(II)Pc have been synthesized and characterized. Detailed analyses of the electronic structure were carried out by spectroscopy, electrochemistry, spectroelectrochemistry, and TD-DFT calculations. A series of experiments demonstrate that the (α,α′-n-OC5H11)8-Ni(II)Pc complex can be used as a catalyst for highly efficient carbonyl reductions.