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	1. Exploring Halogen···Halogen Interactions in Molecular Packing: Benchmark and Theoretical Analysis
	LIU Fang,DU Likai,GAO Jun
	Chemistry 08 December 2015
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	Abstract:The nonbonded halogen halogen (X…X) interactions play an important role in crystal engineering and material sciences. The X…X bond involving two or more halogen centers results in a very interesting donor-acceptor interaction due to their complicated anistropic character, in which each halogen atom could simultaneously be a donor and an acceptor. Their potential energy surface (PES) shows a dual well potential feature. Here, we present a systematic theoretical investigation of the nature of the X…X interactions. The stable geometries, as well as the PES of X…X dimers (FX, X=Cl, Br, I) were extensively studied with a series of theoretical methods. Interestingly, we find that the hybrid wavefunction based approaches (such as MP2.5) are indeed a good choice to obtain improved binding energies (<0.05 kcal/mol error) with reduced computational cost. Among the DFT methods, the statistical errors are significantly dependent on the selected functionals. We anticipate this study could provide us some insights on the future understanding of the feature of X…X interactions in molecular packing.
	TO cite this article:LIU Fang,DU Likai,GAO Jun. Exploring Halogen···Halogen Interactions in Molecular Packing: Benchmark and Theoretical Analysis[OL].[ 8 December 2015] http://en.paper.edu.cn/en_releasepaper/content/4668647


	2. Unexpected Solvent Effects in Controlling Stereoselectivity and Product Distribution: Catalyst-free Reaction of Propranolol with (S)-2-acetoxy-succinic Acid Divinyl Ester
	ZHANG Qingyi,LIN Xianfu
	Chemistry 03 December 2015
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	Abstract:The stereoselectivity and product distribution of catalyst-free reaction of propranolol with (S)-2-acetoxy-succinic acid divinyl ester are shown to be solvent-dependent. In moderate polar solvents, propranolol undergo regioselective acylation and (R)-propranolol vinyl ester spontaneously cyclize, so as to provide the remained (S)-propranolol vinyl ester with high 97% de value. The intramolecular hydrogen bond between the carbonyl group and the propranolol's hydroxy functionality affects the cyclization activity of (R)- or (S)-propranolol vinyl ester in different solvents. However, strong polar solvent are favorable for the cyclization of both (R)- and (S)-propranolol vinyl ester. Distribution of obtained six- or seven-membered morpholinone derivatives was dependent on the nature of the solvent. The best result was the selective formation of 3-morpholinone derivatives in 96% yields. A tandem process of transesterification and β-elimination/Michael addition is a tentative mechanism basing on some designed experiments.
	TO cite this article:ZHANG Qingyi,LIN Xianfu. Unexpected Solvent Effects in Controlling Stereoselectivity and Product Distribution: Catalyst-free Reaction of Propranolol with (S)-2-acetoxy-succinic Acid Divinyl Ester[OL].[ 3 December 2015] http://en.paper.edu.cn/en_releasepaper/content/4667116

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	3. Comparative Studies of Three Synthetic Routes of Enzymatic Multicomponent Reactions (MCRs) for Strongly Fluorescent Spirooxazino Derivatives
	CHEN Xiaoyang,LIN Xianfu
	Chemistry 03 December 2015
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	Abstract:Enzymatic multicomponent reactions are very powerful for complicated organic synthesis with environmental friendly, highly efficient and selective characters. Herein, we designed and compared three routes of enzymatic MCRs for simple and efficient synthesis of complicated spirooxazinos derivatives, and one more efficient synthesis methodology for the target compounds than before was developed. Reaction conditions such as enzymes, enzyme concentration, amides and ratio of substrates were screened, and 15 spirooxazino derivatives were obtained in moderate to good yield. All of these novel spirooxazinos have strong fluorescence emission ability and high quantum yields, providing great application potential in photoactive materials. Furthermore, particularly interesting is that chiral spirooxazino could also be obtained through a developed two-enzymatic MCRs process in one pot.
	TO cite this article:CHEN Xiaoyang,LIN Xianfu. Comparative Studies of Three Synthetic Routes of Enzymatic Multicomponent Reactions (MCRs) for Strongly Fluorescent Spirooxazino Derivatives[OL].[ 3 December 2015] http://en.paper.edu.cn/en_releasepaper/content/4666965


	4. Study on extraction and recovery of almond (Prunus armeniaca L.) protein using aqueous polyethylene glycol as the solvent
	Ge Xianli,Shi Ting,Wang Huan,Zhang Zhiqi
	Chemistry 02 December 2015
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	Abstract:A new method for almond protein extraction and recovery was developed. The extraction efficiencies of different solvents, such as sodium hydroxide, sodium chloride, polyethylene glycol (PEG) 200, PEG 400, and PEG 600 aqueous solutions, were investigated and PEG 200 showed the highest extraction efficiency. The PEG-based microwave-assisted extraction (MAE) parameters were then optimized by using response surface methodology. The optimal extraction parameters were as follows: PEG 200 concentration, 25% (w/w); liquid to solid ratio, 1:22 g/mL; microwave power, 120 W; extraction temperature, 45 C; and extraction time 4 min. At these parameters, the actual average extraction yield was 93.75±3.15%. Subsequently, the almond protein was recovered from the extraction solution containing PEG with an isoelectric point-ethanol synergy precipitation protocol. The combined technique integrated the speed of isoelectric point precipitation with the completeness of alcohol precipitation. The precipitation rate of almond protein was 98.81% with a time of 3-5 min.
	TO cite this article:Ge Xianli,Shi Ting,Wang Huan, et al. Study on extraction and recovery of almond (Prunus armeniaca L.) protein using aqueous polyethylene glycol as the solvent[OL].[ 2 December 2015] http://en.paper.edu.cn/en_releasepaper/content/4667951


	5. Mechanistic Studies of Rh(III)-Catalyzed C-H Olefination of Pyridines and Quinolines Promoted by Cu(OAc)2
	ZHOU Jun,ZHANG Shuo-Qing,LI Bo,SHI Bing-Feng
	Chemistry 01 December 2015
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	Abstract:Detailed investigations towards the mechanistic studies of our previous work on Rh(III)-catalyzed C-H olefination of pyridines and quinolines are reported here. A working hypothesis was proposed for based on experimental and computional studies. The key reaction intermediate 11a was isolated and determined by X-ray crystallography, displaying a dimeric copper coordinated at the pyridine nitrogen. The KIE studies indicates that the cleavage of the C-H bond was not involved in the rate-determining step. The DFT calculations show the orientation of -CO- benefits its function as a directing group and promoted the following reaction. In addtion, controlled experiments have also been conducted. These studies indicate that Cu(OAc)2 might serve as both a convenient oxidant and Lewis acid.
	TO cite this article:ZHOU Jun,ZHANG Shuo-Qing,LI Bo, et al. Mechanistic Studies of Rh(III)-Catalyzed C-H Olefination of Pyridines and Quinolines Promoted by Cu(OAc)2[OL].[ 1 December 2015] http://en.paper.edu.cn/en_releasepaper/content/4665182


	6. Conformation and charge co-modulated ultrasensitive biosensor based on single nanopore channel
	Cai Sheng-Lin,Zheng Yu-Bin,Cao Shuo-Hui,Cai Xiu-Hong,Li Yao-Qun
	Chemistry 28 November 2015
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	Abstract:In this manuscript, we have demonstrated the proof-of-concept of the conformation and surface charge co-modulated ion transport inside a synthetic nanopore engineered by a single stimulus. We integrated an ATP binding aptamer (ABA) into a single glass conical nanopore channel and achieved the simultaneous transitions involving both conformation and charge densities upon the presence of ATP. The synergistic effect of pore size and surface charge has largely enhanced the response efficiency of nanopore. Based on this property, we further developed an ultrasensitive biosensing platform for the detection of ATP with a detection limit down to 0.36 pM (S/N=3).This biomimetic nanodevice exhibited excellent selectivity. This work not only facilitates a better understanding of the ionic transport processes in biological ion channels but also advances their real-world applications in biosensors and actuators.
	TO cite this article:Cai Sheng-Lin,Zheng Yu-Bin,Cao Shuo-Hui, et al. Conformation and charge co-modulated ultrasensitive biosensor based on single nanopore channel[OL].[28 November 2015] http://en.paper.edu.cn/en_releasepaper/content/4666710


	7. Enantioselective Synthesis of Polysubstituted Tetrahydroquinolines via an Organocatalytic Asymmetric Cascade Reaction
	LUO Yongchun,HAN Ronggang,XU Pengfei
	Chemistry 27 November 2015
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	Abstract:Based on the principles of organocatalysis. An enantioselective and efficient catalytic method for synthesis of polysubstituted tetrahydroquinolines via an aldol/nucleophilic addition cascade reaction was developed. This domino process affords a series of tetrahydroquinoline products with good yields (up to 89%) and high diastereo- and enantiocontrol (dr up to >25:1, ee up to 97%). The structre of the products was characterized by NMR, IR, HR Ms and X-ray differaction. In addition, using some simple reactions, the product structure can be easily modified.
	TO cite this article:LUO Yongchun,HAN Ronggang,XU Pengfei. Enantioselective Synthesis of Polysubstituted Tetrahydroquinolines via an Organocatalytic Asymmetric Cascade Reaction[OL].[27 November 2015] http://en.paper.edu.cn/en_releasepaper/content/4665107


	8. Intermolecular 1,3-Dipolar Cycloaddition Reactions of Chiral Cyclic Nitrones with Alkenes
	LUO Yongchun,CHENG Ruiling,XU Pengfei
	Chemistry 27 November 2015
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	Abstract:A efficient 1,3-dipolar cycloaddition reaction between the new chiral cyclic nitrones and alkenes was studied. After the optimization of reaction conditions, a series of valuable chiral isoxazolidine products were prepared with high yields. The structre of the products was characterized by NMR, IR and HR Ms. In addition, according to the analysis of the reaction's transition state, the stereoselevtivity of this cycloaddition and the absolute configuration of cycloadducts was explained reasonably.
	TO cite this article:LUO Yongchun,CHENG Ruiling,XU Pengfei. Intermolecular 1,3-Dipolar Cycloaddition Reactions of Chiral Cyclic Nitrones with Alkenes[OL].[27 November 2015] http://en.paper.edu.cn/en_releasepaper/content/4665101


	9. Silver(I) complexes with halo-substituted cyanoanilines: Synthesis, characterization and antibacterial activities
	Hao-Kun Yuan,Wei Qian,Zhi-Peng Zhao,Rui-Qin Fang
	Chemistry 26 November 2015
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	Abstract:Four novel Ag(I) complexes, [Ag(L1)2]NO3 (1), [Ag(L2)NO3] (2), [Ag(L3)3]NO3 (3) and [Ag(L4)2]NO3 (4) with ligand derived from halo-contained cyanoanilines (L1 = 4-amino-3-fluorobenzonitrile, L2 = 4-amino-3-chlorobenzonitrile, L3 = 4-amino-3-bromobenzonitrile, L4 = 4-amino-2-bromobenzonitrile) were designed, synthesized and characterized by C, H, N elemental analysis and single crystal X-ray diffraction. Complexes 1 to 4 crystallized in triclinic space group C2/c, P2(1)/n, P-1 and C2/c, respectively. In 1 and 4, Ag+ is 4-coordinated by L1 or L4 ligands to form 1D ∞{[Ag(L1/L4)2]+} polymeric cations. In 2, Ag+ is 3-coordinated by two L2 ligands and one NO3- to form a 1D ∞{[Ag(L2)NO3]}zigzag chain. In 3, Ag+ is 4-coordinated by L3 to form a dinuclear [Ag(L3)3]+ cation. The NO3- anion acts as a 4-connector bridging group in 1 and 3, and as a 5-connector bridging group in 2 and 4. The intermolecular hydrogen bonds and Ag???O weak interactions play important roles in forming 3D networks of 1 to 4. In addtion, the antibacterial activities for complexes 1-4 were evaluated against B. subtilis, S. aureus and E. coli with MTT method. The antibacterial results indicated that complex 2 showed best inhibitory activities against the test bacterial strains, which was superior to the positive control chloramphenicol.
	TO cite this article:Hao-Kun Yuan,Wei Qian,Zhi-Peng Zhao, et al. Silver(I) complexes with halo-substituted cyanoanilines: Synthesis, characterization and antibacterial activities[J].


	10. A simple flourescence spectroscopic approach for simultaneous and rapid detection of four polycyclic aromatic hydrocarbons (PAH4) in vegetable oil
	Liu Yi-Hong,Wu Ping-Ping,Liu Qian,Luo He-Dong,Cao Shuo-Hui,Lin Guo-Chun,Fu Dong-Sai,Zhong Xiu-Di,Li Yao-Qun
	Chemistry 24 November 2015
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	Abstract:Based on the conclusions of United States Environmental Protection Agency (USEPA), the four polynulear aromatic hydrocarbons (PAH4) Chrysene, benzo(a)pyrene (BaP), benzo(a)anthracene (BaA), and benzo(b)fluoranthene (BbF) are new markers for the occurrence of PAHs in food. Vegetable oil is a type of food which easy to be contaminated by PAHs due to the raw material pollution and the imperfections in processing technology. Hence, it is of importance to establish efficient method for rapid determination of PAH4 in vegetable oil. In this research, second-derivative nonlinear variable-angle-matrix isopotential synchronous fluorescence spectroscopic approach has been proposed for simultaneous and rapid determination of Chrysene, BaA, BaP and BbF in vegetable oil with ultrasonic-assisted extraction. This method is capable of resolving the spectra of four PAHs well. The limits of detection (LODs) for Chrysene, BaA, BaP and BbF were 13.0, 8.64, 0.16 and 7.68 μg/kg, respectively. The recoveries in various oil samples for Chrysene, BaA, BaP and BbF were 86.2 ± 15.3, 93.8 ± 11.7, 93.9 ± 12.1 and 94.3 ± 7.4 %, respectively, at the spiked levels of 10 ~ 400 μg/kg. The relative standard deviations (RSDs) achieved for Chrysene, BaA, BaP and BbF were 3.0, 8.4, 6.3 and 7.2 %, respectively. The established method is simple, economical and reliable, and provides an attractive alternative for the simultaneous and rapid determination PAH4 in vegetable oil samples.
	TO cite this article:Liu Yi-Hong,Wu Ping-Ping,Liu Qian, et al. A simple flourescence spectroscopic approach for simultaneous and rapid detection of four polycyclic aromatic hydrocarbons (PAH4) in vegetable oil[OL].[24 November 2015] http://en.paper.edu.cn/en_releasepaper/content/4662252

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