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Two New Inclusion 1,4-Butylenediphosphonates with 3D Hydrogen-bonded Frameworks

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Chinese Journal of Structural Chemistry 2004年第8期23卷 855-861页

作者：傅瑞标吴新涛胡胜民杜文新张建军 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

Two new inclusion 1,4-butylenediphosphonates with three-dimensional hydrogen- bonded frameworks have been synthesized and determined by single-crystal X-ray diffraction. In compound 1, the two-dimensional cationic substructures interpenetrate into the anionic framework, and in compound 2, the cations are encapsulated in the three-dimensional framework. Crystal 1 (C14H24N2O8P2) belongs to triclinic, space group P?with a = 9.4645(2), b = 9.6490(2), c = 11.9479(3) ? = 79.7420(10), b = 73.5650(10), = 63.8420(10), V = 937.55(4) 3, Z = 2, Mr = 410.29, Dc = 1.453 g/cm3, m(MoKa) = 0.276 mm-1, F(000) = 432, the final R = 0.0465 and wR = 0.1304 for 3274 independent reflections. Crystal 2 (C18H26N2O10P2) is of monoclinic, space group P21/c with a = 9.7069(12), b = 16.227(2), c = 6.9339(9) ? b = 98.834(3), V = 1079.2(2) ?, Z = 2, Mr = 492.35, Dc = 1.515 g/cm3, m(MoKa) = 0.261 mm-1, F(000) = 516, the final R = 0.0611 and wR = 0.1162 for 1871 independent reflections.

关键词： crystal structure 1 4-butylenediphosphonates hydrogen-bonded frameworks

Laser Flash Photolysis on Electron Transfer Reactions between 1,8-Dihydroxyanthraquinone with Adenine and Cytosine

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Chinese Journal of Chemical Physics 2013年第5期26卷 498-503,I0003页

作者： Xiang Liu Lin Chen Qiao-hui Zhou Xiao-guo Zhou Shi-lin Liu Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics University of Science and Technology of China Hefei 230025 China

Electron transfer （ET） reactions between 1,8-dihydroxyanthraquinone （DHAQ） and two DNA bases, adenine （A） and cytosine （C）, have been investigated in CH3CN/H20 solution with nanosecond time-resolved laser flash photolysis. After irradiation at 355 nm, the triplet DHAQ is produced via intersystem crossing and reacts with two nucleobases. ET processes for both reactions have been definitely identified, in which two bases play a significant role of electron donor. Based on the measured decay dynamics of various intermediates and the corresponding quenching rates, an initial ET process followed by a secondary proton-transfer reaction is suggested for both the overall reactions. By plotting the observed quenching rate against the concentration of two DNA bases, the bimolecular quenching rate constants are determined as 9.0-10s L/（mol.s） for the 3DHAQ＊＋C reaction and 3.3x10^8 L/（mol.s） for the 3DHAQ＊＋A reaction, respectively.

关键词： Electron transfer Proton transfer 1 8-dihydroxyanthraquinone Laser flashphotolysis Adenine Cytosine

Reductive amination of 1,6-hexanediol with Ru/Al2O3 catalyst in supercritical ammonia

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Science China Chemistry 2017年第7期60卷 920-926页

作者： Yan Li Haiyang Cheng Chao Zhang Bin Zhang Tong Liu Qifan Wu Xinluona Su Weiwei Lin Fengyu Zhao State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Laboratory of Green Chemistry and Process Changchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022China Department of Environmental Science and Engineering Heilongfiang UniversityHarbin 150080China

Hexamethylenediamine(HMDA) is an important reagent for the synthesis of Nylon-6,6, and it is usually produced by the hydrogenation of adiponitrile using a toxic reagent of hydrocyanic acid. Herein, we developed an environmental friendly route to produce HMDA via catalytic reductive amination of 1,6-hexanediol(HDO) in the presence of hydrogen. The activities of several heterogeneous metal catalysts such as supported Ni, Co, Ru, Pt, Pd catalysts were screened for the present reaction in supercritical ammonia without any additives. Among the catalysts examined, Ru/Al_2O_3 presented a high catalytic activity and highest selectivity for the desired product of HMDA. The high performance of Ru/Al_2O_3 was discussed based on the Ru dispersion and the surface properties like the acid-basicity. In addition, the reaction parameters such as reaction temperature,time, H_2 and NH_3 pressure were examined, and the reaction processes were discussed in detail.

关键词： 1 6-hexanediol hexamethylenediamine supercritical ammonia reductive amination Ru/Al2O3

Oxidation reactivity of 1,2-bis(2,4,6-tribromophenoxy)ethane(BTBPE)by CompoundⅠmodel of cytochrome P450s

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Journal of Environmental Sciences 2017年第12期29卷 11-21页

作者： Zhongyu Wang Zhiqiang Fu Qi Yu Jingwen Chen Key Laboratory of Industrial Ecology and Environmental Engineering(MOE) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

Alternative brominated flame retardants（BFRs） have become prevalent as a consequence of restrictions on the use of polybrominated diphenyl ethers（PBDEs）. For risk assessment of these alternatives, knowledge of their metabolism via cytochrome P450 enzymes is *** have previously proved that density functional theory（DFT） is able to predict the metabolism of PBDEs by revealing the molecular mechanisms. In the current study, the reactivity of 1,2-bis（2,4,6-tribromophenoxy）ethane and structurally similar chemicals with the Compound I model representing the active site of P450 enzymes was investigated. The DFT calculations delineated reaction pathways which lead to reasonable explanations for products that were detected by wet experiments, meanwhile intermediates which cannot be determined were also proposed. Results showed that alkyl hydrogen abstraction will lead to bis（2,4,6-tribromophenoxy）ethanol, which may undergo hydrolysis yielding2,4,6-tribromophenol, a neurotoxic compound. In addition, a general pattern of oxidation reactivity regarding the 2,4,6-tribromophenyl moiety was observed among several model compounds. Our study has provided insights for convenient evaluation of the metabolism of other structurally similar BFRs.

关键词： 1 2-Bis(2 4 6-tribromophenoxy)ethane(BTBPE) Alternative brominated flame retardants Metabolic reactivity P450 Compound Ⅰ

POLYAMIDES WITH PENDANT 1,3,4-OXADIAZOLE AND PYRIDINE MOIETIES

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Chinese Journal of Polymer Science 2012年第1期30卷 112-121页

作者： Yagoub Mansoori Behzad Koohi-Zargar Hemayat Shekaari Mohammad Reza Zamanloo Gholam Hassan Imanzadeh Department of Applied Chemistry College of Science University of Mohaghegh ArdabiliArdabil56199-11367Iran

A novel aromatic diamine,2-（5-（3,5-diaminophenyl）-l,3,4-oxadiazole-2-yl）pyridine（POBD）,containing a pyridine ring and a 1,3,4-oxadiazole moiety,was *** was used in a polycondensation with various aromatic and aliphatic diacid chlorides to generate a series of new aromatic polyamides with pendant 1,3,4-oxadiazole *** prepared polyamides were characterized by IR,elemental analysis and through the synthesis of model *** properties of the synthesized polyamides have been studied by DSC,TGA and inherent viscosity measurements. Relatively high inherent viscosity values（0.76-1.62 dL/g,in 0.125%H_2SO_4 at 25℃） were observed for these compounds. Number average molecular weight（M_n） of the polymers was measured by vapor phase osmometry（VPO）.The introduction of bulky side chains in the structure of aromatic polyamides led to increased solubility of these polymers in common polar and aprotic solvents,such as DMF,DMSO,NMP and DMAc,which allowed thin films to be cast from polymer solutions. The highest molecular weight（M_n = 51190） was observed for polymer（DC）,which was prepared from pyridine-2,6-dichlorocarbonyl.

关键词： Polyamide 1 3 4-Oxadiazole Inherent viscosity Vapor phase osmometry Polycondensation

Absorption characteristics of new solvent based on a blend of AMP and 1,8-diamino-p-menthane for CO_2 absorption

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Journal of Environmental Sciences 2012年第5期24卷 897-902页

作者： Sang-Sup Lee Seong-Man Mun Won-Joon Choi Byoung-Moo Min Sang-Won Cho Kwang-Joong Oh Department of Environmental Engineering Chungbuk National University Department of Environmental Engineering Pusan National University Corporate R&D Institute Fuel Cell System Development Team Doosan Heavy Industries & Construction Greenhouse Gas Research Center Korea Institute of Energy Research Department of Energy and Environment Korea Polytechnic VII College

Aqueous 1,8-diamino-p-menthane （KIER-C3） and commercially available amine solutions were tested for CO2 absorption. A 2-amino-2-methyl-1-propanol （AMP） solution with an addition of KIER-C3 showed 9.3% and 31.6% higher absorption rate for CO2 than the AMP solution with an addition of monoethanolamine （MEA） and ammonia （NH3）, respectively. The reaction rate constant for CO2 absorption by the AMP/KIER-C3 solution was determined by the following equation： k2,AMP/C3 = 7.702×106 exp （-2248.03/T）. A CO2 loading ratio of the AMP/KIER-C3 solution was also 2 and 3.4-times higher than that of the AMP/NH3 solution and the AMP/MEA solution, respectively. Based on the experimental results, KIER-C3 may be used as an excellent additive to increase CO2 absorption capability of AMP.

关键词： carbon dioxide absorption rate and capacity 1 8-diamino-p-menthane 2-amino-2-methyl-1-propanol

Low temperature one-pot synthesis of 1,1-diethoxyethane from ethanol on Bi/BiCeO_(x)with strong metal-support interactions

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Nano Research 2023年第3期16卷 3709-3718页

作者： Zhe An Jiayu Liu Meng Cao Jian Zhang Yanru Zhu Hongyan Song Xu Xiang Jing He State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

The direct conversion of ethanol to 1,1-diethoxyethane(DEE)through one-pot dehydrogenation-acetalization has attracted broad interest from both academia and *** on thermodynamics,the oxidative dehydrogenation of alcohol to acetaldehyde requires high temperature to activate oxygen to realize the C-H cleavage,while the acetalization of acetaldehyde with ethanol is exothermic reversible reaction favorable at low *** mismatching of the reaction condition for the two consecutive steps makes it a great challenge to achieve both high ethanol conversion and high DEE *** work reports a highly efficient bi-functional catalysis by Bi/BiCeO_(x)for one-pot oxidative dehydrogenation-acetalization route from ethanol to DEE under 150℃and ambient pressure,affording a selectivity of 98.5%±0.5%to DEE at an ethanol conversion of 87.0%±1.0%.An efficient tandem catalysis has been achieved on the interfacial Bi^(δ)+-Ov-Ce^(III)sites in Bi/BiCeO_(x)established by strong metal-support interaction,in which Biδ+-Ov-sites contribute to the oxidative dehydrogenation of ethanol at mild temperature,and-Ov-CeIII sites to the subsequent acetalization between the generated acetaldehyde and ethanol.

关键词： ethanol conversion 1 1-diethoxyethane strong metal-support interaction Biδ+-Ov-CeIII sites

Stereoselective synthesis of substituted 1,3-dienes from propargylic esters: electrophilic-metal or redox catalysis?

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Science China Chemistry 2024年第5期67卷 1384-1396页

作者： Mengfu Dai Liangliang Song Liang-An Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China

1,3-Diene architectures are not only widely present in natural products, pharmaceuticals, and functional organic materials but also serve as versatile building blocks to furnish important functionalized molecules in synthetic chemistry due to conjugated repeating C=C units. Accordingly, various strategies to access substituted 1,3-dienes in a stereoselective manner have been developed. However, chemo-, regio-and stereoselective synthesis of highly substituted 1,3-dienes still remains elusive and challenging. Readily available propargylic esters have emerged as an appealing class of synthetic intermediates for accessing functionalized 1,3-dienes, especially challenging tri-or tetrasubstituted variants, via transition-metal catalysis, including electrophilic metal and redox neutral catalysis. This review, for the first time, systematically highlights recent advances in transitionmetal catalyzed synthesis of substituted 1,3-dienes from propargylic esters, discusses the mechanisms and synthetic utilities, and gives the remaining challenges and potential opportunities in this field.

关键词： 1 3-diene propargylic ester Lewis acid redox catalysis transition metal

THERMALLY STABLE POLYMERS CONTAINING 1,3,4-OXADIAZOLE UNITS OBTAINED FROM HUISGEN REACTION

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Chinese Journal of Polymer Science 2012年第1期30卷 36-44页

作者： Y.Mansoori G.Barghian B.Koohi-Zargar Gh.Imanzadeh M.Zamanloo Department of Applied Chemistry College of Science University of Mohaghegh ArdabiliArdabil 56199-11367Iran

Thermally stable polymers containing 1,3,4-oxadiazole units have been synthesized through Huisgen reaction of the aromatic/aliphatic bis-tetrazole compounds with the aromatic/aliphatic bis-acid chlorides in pyridine as *** obtained polymers are insoluble or slightly soluble even in polar aprotic solvents such as DMSO and *** high inherent viscosity values（0.61-1.33 dL/g,in 0.125%H_2SO_4 at 25℃） were observed for these *** analyses of the polymers using DSC and TGA techniques showed that the polymers have improved thermal *** glass transition temperature has not been observed in the fully aromatic polymers,but the polymers obtained from 5-[6-（1H-tetrazol -5-yl）hexyl]-lH-tetrazole（Ⅳ） showed very clear T_g.A model reaction was also investigated and the resulting bis-1,3,4-oxadiazole compound was characterized by conventional spectroscopy methods.

关键词： 1 3 4-Oxadiazole Thermally stable polymers Bis-tetrazole Huisgen reaction