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Synthesis of bis(indolyl) methanes using aluminiumoxide(acidic) in dry media 被引量:7
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作者 Sandip A.Sadaphal Amol H.Kategaonkar +1 位作者 Vilas B.Labade Murlidhar S.Shingare 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期39-42,共4页
Heterogeneous catalyst aluminium oxide(acidic) is found to be an effective catalyst for the solvent-free condensation reaction of indole with aldehydes in microwave irradiation with shorter reaction time and higher yi... Heterogeneous catalyst aluminium oxide(acidic) is found to be an effective catalyst for the solvent-free condensation reaction of indole with aldehydes in microwave irradiation with shorter reaction time and higher yields. 展开更多
关键词 Aluminium oxide(acidic) INDOLE ALDEHYDES bis(indolyl methanes Microwave irradiation Dry media
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Efficient synthesis of bis(indolyl) methanes catalyzed by(PhCH_2PPh_3)^+Br_3^- under solvent-free conditions 被引量:5
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作者 Farhad Shirini Mohaddeseh Safarpoor Langroodi Masoumeh Abedini 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第11期1342-1345,共4页
Benzyltriphenylphosphonium tribromide(BTPTB) has been applied as an efficient catalyst for the preparation of bis(indolyl)-methanes (BIMs) via electrophilic substitution of indoles with aldehydes in the absence ... Benzyltriphenylphosphonium tribromide(BTPTB) has been applied as an efficient catalyst for the preparation of bis(indolyl)-methanes (BIMs) via electrophilic substitution of indoles with aldehydes in the absence of solvent. 展开更多
关键词 Benzyltriphenylphosphonium tnbroraide ALDEHYDES INDOLES bis(indolyl methanes Solvent-free conditions
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Oxalic acid as a catalyst for efficient synthesis of bis-(indolyl)methanes,and 14-aryl-14H-dibenzo[a,j]xanthenes in water 被引量:2
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作者 Nagnnath D.Kokare Jaiprakash N.Sangshetti Devanand B.Shinde 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第10期1186-1189,共4页
A simple, efficient, and environment benign route was developed for the preparation of bis-(indolyl)methanes and 14-aryl-14H- dibenzo[aj]xanthenes from condensation of various aromatic aldehydes or ketones with indo... A simple, efficient, and environment benign route was developed for the preparation of bis-(indolyl)methanes and 14-aryl-14H- dibenzo[aj]xanthenes from condensation of various aromatic aldehydes or ketones with indole, and 2-naphthol, respectively, using oxalic acid catalyst in aqueous medium. Use of cheap and easily available catalyst, better yields and simple reaction protocol are the advantages of the present method. 展开更多
关键词 Oxalic acid bis-(indolylmethanes 14-Aryl-14H-dibenzo[a j]xanthenes Aldehydes
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n-Dodecylbenzene Sulfonic Acid (DBSA) as a Novel Brønsted Acid Catalyst for the Synthesis of Bis(indolyl)methanes and Bis(4-hydroxycoumarin-3-yl)methanes in Water
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作者 Balu Pawar Vinod Shinde Atul Chaskar 《Green and Sustainable Chemistry》 2013年第2期56-60,共5页
n-Dodecylbenzene sulfonic acid (DBSA) as a novel, biodegradable, and efficient Br?nsted acid catalyst used for the reaction of indoles/4-hydroxy coumarin with aldehydes to obtain a bis(indolyl)methanes/bis(4-hydroxyco... n-Dodecylbenzene sulfonic acid (DBSA) as a novel, biodegradable, and efficient Br?nsted acid catalyst used for the reaction of indoles/4-hydroxy coumarin with aldehydes to obtain a bis(indolyl)methanes/bis(4-hydroxycoumarin-3-yl)methanes, respectively. The catalyst exhibited remarkable activity, and tolerated a wide variety of functional groups providing the desired bis(indolyl)methanes and bis(4-hydroxycoumarin-3-yl)methanes in good to excellent yield (70%-96%) in water. 展开更多
关键词 n-Dodecylbenzene Sulfonic Acid (DBSA) Indole Aldehyde bis(indolyl)methane bis(4-hydroxycoumarin-3-yl)methanes
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Efficient and Eco-friendly Process for the Synthesis of Bi(indolyl)methanes Catalyzed by Sodium Hydrogensulfate Monohydrate in Ionic Liquid n-Butylpyridinium Tetrafluoroborate 被引量:1
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作者 Li Ping ZHANG Yi Qun LI Mei Yun ZHOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期723-726,共4页
Efficient electrophilic substitution reaction of indoles with various aromatic aldehydes were carried out with a catalytic amount of sodium hydrogensulfate monohydrate (NaHSO4·H20) in ionic liquid n-butylpyridi... Efficient electrophilic substitution reaction of indoles with various aromatic aldehydes were carried out with a catalytic amount of sodium hydrogensulfate monohydrate (NaHSO4·H20) in ionic liquid n-butylpyridinium tetrafluoroborate ([Bpy]BF4) to afford the corresponding bi(indolyl)methanes in excellent yields. The notable advantages of this protocol in terms of low cost of catalyst and ionic liquid, mild conditions, simple operation, short reaction time, high yields and recycling of the ionic liquid. 展开更多
关键词 bi(indolylmethane ionic liquid sodium hydrogen sulfate.
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Heterotetranuclear Cu_2~IPd_2~Ⅱ Complex with Bis(diphenylphosphino)methane and Diethyldithiocarbamate 被引量:2
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作者 SITU Yue HUANG Shao-Bin (Department of Applied Chemistry, South China University of Technology, Guangzhou, Guangdong 510640, China) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第4期435-438,共4页
Self-assembly between the building blocks of Pd(Et2dtc)2 (Et2dtc = diethyldithio- carbamate) and [Cu2(m-dppm)2(MeCN)2]2+ (dppm = bis(diphenylphosphino)methane) gave a new heterotetranuclear complex [Cu2Pd2(m-dppm)2(m-... Self-assembly between the building blocks of Pd(Et2dtc)2 (Et2dtc = diethyldithio- carbamate) and [Cu2(m-dppm)2(MeCN)2]2+ (dppm = bis(diphenylphosphino)methane) gave a new heterotetranuclear complex [Cu2Pd2(m-dppm)2(m-Et2dtc)2(m3-Et2dtc)2](ClO4)2H2O (C70H86Cl2Cu2- N4O9P4Pd2S8, Mr = 1932.56), and its crystal structure has been determined by X-ray crystallo- graphy. It crystallizes in triclinic, space group P with a = 11.9834(6), b = 12.5624(6), c = 14.5603(8) ? a = 101.393 (1), b = 103.300 (1), g = 96.310(1), V = 2063.2(2) 3, Z = 1, Dc = 1.544 g/cm3, m(MoKa) = 1336 cm-1 and F(000) = 978. The total and unique reflections are 8710 and 5400, respectively. The structure was refined to R = 0.0860 and wR = 0.1996 for 3914 observed reflections with I > 2s(I). The title complex consists of the cation [Cu2Pd2(m-dppm)2(m-Et2dtc)2(m3- Et2dtc)2]2+, anion ClO4- and solvate H2O. The Pd(Ⅱ) atoms are located at the approximately square-planar environments with PS3 donors and the Cu(I) atoms display distorted tetrahedral geometries. 展开更多
关键词 bis(diphenylphosphino)methane DIETHYLDITHIOCARBAMATE copper crystal structure PALLADIUM
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A New Ternary Fluorescent Europium Complex with Bis(Diphenyl Phosphine Oxide) Methane and Thenoyltrifluoroacetone 被引量:1
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作者 高希存 曹红 +2 位作者 姚光庆 黄春辉 黄玲 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第3期170-173,共4页
A fluorescent ternary europium complex containing bis (diphenyl phosphine oxide) methane which functioned as both a neutral and anion ligand, and thenoyltrifluoroacetonato anion was synthesized and characterized by e... A fluorescent ternary europium complex containing bis (diphenyl phosphine oxide) methane which functioned as both a neutral and anion ligand, and thenoyltrifluoroacetonato anion was synthesized and characterized by elemental analysis, DTA TG analysis, UV Vis, FT IR and MS spectroscopy. The chemical formula is proved to be Eu(TTA)(MPPO)(HMPPO)·(NO 3)·2H 2O. Its luminescence quantum efficiency(in acetonitrile, 26 3%) is approximately the same as that of the commonly used red emission luminescent compound, Eu(TTA) 3(TPPO) 2 (TPPO is triphenyl phosphine oxide). The new complex has comparatively long fluorescence lifetime. 展开更多
关键词 Rare earths Europium bis (diphenyl phosphine oxide) methane THENOYLTRIFLUOROACETONE Fluorescence
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Construction of a New Two-fold Interpenetrated Three-dimensional Cobalt(Ⅱ)Coordination Polymer Based on 2,5-Thiophenedicarboxylic Acid and Bis(imidazol-1-yl)methane 被引量:1
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作者 薛丽平 崔佳佳 +2 位作者 张婷 高越 姚佳昕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第7期1133-1138,共6页
A cobalt coordination polymer, {[Co2(tdc)2(bimm)2]·(3 DMF)}n, was synthesized based on 2,5-thiophenedicarboxylic acid(H2 tdc) and bis(imidazol-1-yl)methane(bimm) mixed ligands. The asymmetric unit of ... A cobalt coordination polymer, {[Co2(tdc)2(bimm)2]·(3 DMF)}n, was synthesized based on 2,5-thiophenedicarboxylic acid(H2 tdc) and bis(imidazol-1-yl)methane(bimm) mixed ligands. The asymmetric unit of the complex contains two Co2+) cations, two tdc2-dianions, two neutral bimm ligands, and three free DMF molecules. In the complex, deprotonated tdc2-dianions alternately bridge the adjacent Co2+ cations to generate chains, which are further connected by the flexible bimm ligands to form a 3 D structure containing adamantanoid-like subunits. In topology, the structure of 1 represents a 4-connected uninodal two-fold interpenetrated dia(66) topology. Moreover, the solid UV-Vis absorption spectra of the complex have also been investigated. 展开更多
关键词 cobalt coordination polymer 2 5-thiophenedicarboxylic acid bis(imidazol-1-yl)methane crystal structure dia topology
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Total synthesis of bis-(2,3-dibromo-4,5-dihydroxyphenyl)-methane as potent PTP1B inhibitor 被引量:6
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作者 Jing Li Shu Ju Guo +2 位作者 Hua Su Li Jun Han Da Yong Shi 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第11期1290-1292,共3页
Protein tyrosine phosphatase 1B (PTP1B) plays an important role as a negative regulator and has been proved to be an effective target for the treatment of type 2 diabetes mellitus. Bis-(2,3-dibromo-4,5-dihydroxyphe... Protein tyrosine phosphatase 1B (PTP1B) plays an important role as a negative regulator and has been proved to be an effective target for the treatment of type 2 diabetes mellitus. Bis-(2,3-dibromo-4,5-dihydroxyphenyl)-methane 7 was first reported as a natural bromophenol with significant inhibition against PTP1B which was isolated from red algae Rhodomela conrervoides. Intrigued by its astonishing activity (IC50 = 2.4 μmol/L), compound 7 was synthesized with the overall yield of 24% and evaluated for its PTPIB inhibitory activity compared with natural compound. 展开更多
关键词 Bromophcnol bis-(2 3-dibromo-4 5-dihydroxyphcnyl)-methane PTPIB inhibitor Total synthesis
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Synthesis and Crystal Structure of Bis(μ-bis(diphenyl- phosphino)methane)(μ-benzenethiolate)(acetonitrile) Dicopper(I) Perchlorate Diethylether Solvate
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作者 陈燕丹 张礼仪 陈忠宁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第4期395-398,共4页
The reaction between [Cu2(m-dppm)2(MeCN)4](ClO4)2(dppm = bis(diphenylphos- phino)methane) and [Zn(PhS)2(bpy)] (bpy = 2,2-bipyridine, PhS = benzenethiolate) gave the complex [Cu2(m-dppm)2(m-PhS)(MeCN)]ClO40.5(Et2O)(C58... The reaction between [Cu2(m-dppm)2(MeCN)4](ClO4)2(dppm = bis(diphenylphos- phino)methane) and [Zn(PhS)2(bpy)] (bpy = 2,2-bipyridine, PhS = benzenethiolate) gave the complex [Cu2(m-dppm)2(m-PhS)(MeCN)]ClO40.5(Et2O)(C58H52ClNO4P4SCu20.5Et2O) which was determined by X-ray single-crystal diffraction. The crystal is of orthorhombic, space group P212121 with a = 13.6157(3), b = 20.8022(6), c = 21.3299(6) ? V = 6041.4(3) 3, Mr = 1182.54, Dc = 1.300 g/cm3, F(000) = 2444, m = 0.934 mm-1 and Z = 4. The final R = 0.0773 and wR = 0.1843 for 7744 observed reflections (I > 2s(I)). The dicopper atoms are doubly bridged by dppm as well as one S donor from benzenethiolate. One copper atom is in a distorted trigonal bipyramidal environ- ment, whereas the other adopts a distorted tetrahedral geometry. 展开更多
关键词 copper bis(diphenylphosphino)methane benzenethiolate crystal structure
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Syntheses and Crystal Structures of Two Heterobimetallic Clusters [WOS_3Cu_3I(dmpzm)_2]·2(MeCN)_(0.5) and [WS_4Cu_4I_2(dmpzm)_2]·DMF(dmpzm=Bis(3,5-dimethylpyrazolyl)methane)
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作者 任玉树 陈阳 +5 位作者 李端秀 郭承鑫 乔善宝 李红喜 任志刚 郎建平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期861-868,共8页
The reaction of [Et4N]2WOS3 with three equiv.of CuI and dmpzm in MeCN afforded [WOS3Cu3I(dmpzm)2]·2(MeCN)0.5(1·2(MeCN)0.5) while that of [PPh4]2WS4 with four equiv.of CuI in DMF/MeCN followed by the ... The reaction of [Et4N]2WOS3 with three equiv.of CuI and dmpzm in MeCN afforded [WOS3Cu3I(dmpzm)2]·2(MeCN)0.5(1·2(MeCN)0.5) while that of [PPh4]2WS4 with four equiv.of CuI in DMF/MeCN followed by the addition of two equiv.of dmpzm in MeOH gave rise to [WS4Cu4I2(dmpzm)2]·DMF(2·DMF).Both compounds were characterized by elemental analysis,IR,and single-crystal X-ray diffraction analysis.1·2(MeCN)0.5 crystallizes in triclinic,space group P1-with a = 11.4552(5),b = 11.6735(3),c = 16.2278(9) ,α = 99.537(9),β = 101.986(2),γ = 118.464(13)o,V = 1775.5(3)3,Z = 2,μ = 6.080 mm-1,Dc = 1.983 Mg/m3,T = 193(2) K,C24H35Cu3IN9OS3W,Mr = 1063.22,F(000) = 1018,S = 1.060,R = 0.0376 and wR = 0.0870.2·DMF belongs to the orthorhombic system,space group Pmn21 with a = 22.145(4),b = 11.464(2),c = 7.7370(15) ,V = 1964.2(6)3,Z = 2,μ = 6.865 mm-1,Dc = 2.189 Mg/m3,T = 193(2) K,C25H39Cu4I2N9OS4W,Mr = 1301.72,F(000) = 1226,R = 0.0632,wR = 0.1706 and S = 1.130.1·2(MeCN)0.5 consists of one CuI and two [Cu(dmpzm)]+ fragments that are linked by [WOS3]2-species via six Cu-S bonds,forming a nido-like [WS3Cu3] core.2·DMF contains a saddle-shaped [WS4Cu4] core with two iodides coordinated at two Cu centers in a cis position and two dmpzm ligands being chelated at another two Cu centers in a cis position. 展开更多
关键词 tungsten cluster copper(I) cluster sulfur cluster bis(3 5-dimethylpyrazolyl)methane synthesis crystal structure
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Synthesis and Crystal Structure of [Ni(bdpm)_2(OAc)]_2(N_3)_2·5H_2O(bdpm=Bis(3,5-dimethylpyrazol-1-yl)methane,OAc=CH_3COO^-)
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作者 GAO Hong-Yan LING Yun ZHANG Lei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第9期1115-1119,共5页
A Ni(Ⅱ) complex [Ni(bdpm)2(OAc)]2(N3)2.5H20 (bdpm = bis(3,5-dimethylpyrazol-1-yl)-methane) was synthesized and characterized by elemental analysis, 1R and single-crystal X-ray diffraction. It crystallizes... A Ni(Ⅱ) complex [Ni(bdpm)2(OAc)]2(N3)2.5H20 (bdpm = bis(3,5-dimethylpyrazol-1-yl)-methane) was synthesized and characterized by elemental analysis, 1R and single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group P21/c with a = 18.630(2), b = 16.6624(19), c = 19.821(2) A, fl = 90.146(2)°, V = 6152.9(12) A3, Z = 4, C48H80N22Ni2O9, Mr = 1226.76, Dc = 1.324 g/cm^3, F(000) = 2600 and μ = 0.680 mm^-1. The structure was refined to the final R = 0.0578 and wR = 0.1337 for 10848 independent reflections (Rint = 0.0311) and 6915 observed reflections (1 〉 2σ(I)). The complex contains two asymmetric molecules in the cell with small difference in bond distances and bond angles. Each Ni(Ⅱ) ion is bound by four nitrogen atoms of two chelating bdpm groups in a six-membered boat conformation and two oxygen atoms from one chelating bidentate acetate group to form a distorted octahedral geometry. The complex also contains azide anion outside acting as counteranion and two crystalline water molecules to link two discrete mononuclear cations though hydrogen bonds. 展开更多
关键词 nickel complex bis(3 5-dimethylpyrazol-1-yl)methane crystal structure
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New Green Synthesis and Antineoplastic Activity of Bis (3-Arylimidazolidinyl-1) Methanes
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作者 María Cristina Caterina Isabel A. Perillo +4 位作者 Ximena Villalonga Nicolás Amiano Cristian Payés Mercedes L. Sanchez Alejandra Salerno 《Open Journal of Medicinal Chemistry》 2013年第4期121-127,共7页
A new green synthesis and anti-tumor activity of the series of bis (3-arylimidazolidinyl-1) methanes 1 - 6 are described. The compounds were synthesized from the corresponding N-arylethylenediamine and trioxane as sou... A new green synthesis and anti-tumor activity of the series of bis (3-arylimidazolidinyl-1) methanes 1 - 6 are described. The compounds were synthesized from the corresponding N-arylethylenediamine and trioxane as sources of formaldehyde and the reactions were performed in heterogeneous phase catalyzed by an acidic ion-exchange resin (Amberlyst 15). The compounds were tested with the Sulforhodamine B assay according to the protocol of the National Cancer Institute for several cell lines. The results were expressed as percentage inhibition of growth cell in comparison with the full growth of the cells without treatment. Cytotoxicity on normal cells using the Annexing-PI staining and flow cytometry has been evaluated. The parent compound, bis(3-phenylimidazolidinyl-1)methane 1 and the monohalogenated derivatives 4-chlorophenyl 3 and 3-bromophenyl 5 showed antineoplastic activity, 60%, 82% and 89% inhibition growth cell respectively on the human colon cell line (HCT116). The 4-tolyl derivative 6 presented inhibitory activity (73% inhibition of growth cell) on human lung adenocarcinoma cell line (A549) and 62% on human mammary cell line MCF-7. 展开更多
关键词 bis (3-Arylimidazolidinyl-1) methanes Amberlyst-15 ANTICANCER Activity Cancer Cell LINES Sulforhodamine B
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THE CONDENSATION REACTION OF BIS(PERFLUOROALKANESULFONYL)METHANES WITH AROMATIC ALDEHYDES
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作者 Shi Zheng ZHU Shanghai Institute of organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai,200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期601-604,共4页
The ccndensation reactions occurred when heating bis(perfluoroalkane- sulfonyl)methanes with aromatic aldehydes in acetic acid anhydride and gave high yields of 1-aryl-2,2-di(perfluoroalkanesulfonyl)ethylenes The perf... The ccndensation reactions occurred when heating bis(perfluoroalkane- sulfonyl)methanes with aromatic aldehydes in acetic acid anhydride and gave high yields of 1-aryl-2,2-di(perfluoroalkanesulfonyl)ethylenes The perfluoroalkanesulfonyl groups R_FSO_2 are known as the strongest electron-attracting substituents^(1-2).This property is often used in the activation of C-C multiple and 2,2'-C-H bonds.The synthesis and reactions of perfluoroalkanesulfonyl substituted alkenes and alkynes are of great interest in synthetic organic chemistry^(3-6). Recently,Hanack^7 reported the preparation of 2-aryl-l-(perfluoroalkane- sulfonyl)acrylonitrile R_FSO_2C(CN)=CHAr.However,he failed to obtain the 1,1-di(perfluoroalkanesulfonyl)alkenes by the Knoevenagel reaction of bis(perfluoroalkanesulfonyl)methane with aldehydes. 展开更多
关键词 CF SO PERFLUOROALKANESULFONYL)methaneS WITH AROMATIC ALDEHYDES THE CONDENSATION REACTION OF bis
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SbCl_3 Catalyzed Solventless Synthesis of Bis(indolyl)alkanes under Grinding 被引量:1
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作者 ZHANG Ji-ming XU Rui-ping +1 位作者 TIAN Yan ZHOU Jian-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第6期941-944,共4页
A clean and efficient method for the synthesis of bis(indolyl)alkanes with antimony trichloride(SbCl3) as the catalyst under solvent-free grinding conditions is described. This method provides several advantages, ... A clean and efficient method for the synthesis of bis(indolyl)alkanes with antimony trichloride(SbCl3) as the catalyst under solvent-free grinding conditions is described. This method provides several advantages, such as simple work-up procedure, neutral conditions and high yields. 展开更多
关键词 bis(indolyl)alkane Indole SBCL3 GRINDING
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A Facile Synthesis of Bi- and Tri-(4-dimethylaminophenyl)methane
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期487-487,共1页
关键词 A Facile Synthesis of bi dimethylaminophenyl)methane and Tri
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Modified Ceria-Zirconia Fluorite-Like Catalysts for the Combustion of Methane
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作者 Tatiana Kuznetsova Vladislav Sadykov +5 位作者 Lubsan Batuev Ella Moroz Elena Burgina Vladimir Rogov Vladimir Kriventsov Dmitrii Kochubey 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第3期149-163,共15页
For dispersed ceria-zirconia-based solid solutions prepared via the polymerized complex method and annealed at 700 ℃, effects of bulk doping by Ca, Mn, Co, Bi or Nb cations and surface modification by Mn and Pt on th... For dispersed ceria-zirconia-based solid solutions prepared via the polymerized complex method and annealed at 700 ℃, effects of bulk doping by Ca, Mn, Co, Bi or Nb cations and surface modification by Mn and Pt on their structural features, surface/bulk oxygen reactivity and catalytic activity in methane combustion are considered. With up to 20 mol% doping, a structural type of homogeneous solid solutions of anion-deficient fluorite with disordered anion vacancies is formed. Doping by transition metal cations or Pt increases the mobility and reactivity of the surface/bulk oxygen. A broad variation in specific rates of methane combustion for the studied systems was observed, suggesting structural sensitivity of this reaction. In general, there is no universal relationship between the oxygen mobility, the reactivity and the catalytic activity in methane combustion, which is explained by the factor of specific methane activation on surface active sites. For the Pt-promoted samples, Pt efficiency in methane activation depends on the Pt-support interaction, and the most favorable ones being mixed Pt/MnOx and Pt/NbOx clusters on the surface of the supports that exhibit high lattice oxygen mobilities. 展开更多
关键词 Ce-Zr-O Ca Mn Co bi Nb structural features oxygen reactivity oxygen mobility methane combustion
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甲烷裂解双分散孔催化剂颗粒积碳行为模拟
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作者 王帅 杨学松 +1 位作者 王家兴 刘辉 《中国粉体技术》 CSCD 2024年第1期14-22,共9页
【目的】为了更好地理解催化剂颗粒的积碳行为,分析积碳效应下催化剂颗粒界面反应传质特性,实现对催化剂颗粒的优化设计与调控。【方法】采用颗粒解析模型,考虑积碳引起的孔隙结构动态演变以及反应性能的衰减,分别探讨单分散孔和双分散... 【目的】为了更好地理解催化剂颗粒的积碳行为,分析积碳效应下催化剂颗粒界面反应传质特性,实现对催化剂颗粒的优化设计与调控。【方法】采用颗粒解析模型,考虑积碳引起的孔隙结构动态演变以及反应性能的衰减,分别探讨单分散孔和双分散孔颗粒积碳形成及所引起的孔隙结构演变规律。【结果】积碳失活从多孔颗粒表层向内部核心移动,扩散主导机制转向反应主导机制;相较于单分散孔颗粒,双分散孔颗粒具备更强的抗积碳性能;固定床反应器中催化剂颗粒分布影响积碳行为,壁面处积碳更加严重,更容易导致失活。【结论】选择双分散孔催化剂颗粒对于积碳行为具有改善作用,同时应选择合适的长径比反应器,削弱壁面效应对积碳行为的影响。 展开更多
关键词 积碳 甲烷 裂解 双分散孔 孔隙结构
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A practical synthesis of bis(indolyl)methanes catalyzed by BF_3·Et_2O 被引量:7
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作者 Xia-Fei Xu Yan Xiong +4 位作者 Xue-Ge Ling Xi-Mi Xie Jie Yuan Shu-Ting Zhang Zhong-Rong Song 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第3期406-410,共5页
Practical BF3.Et20 catalyzed reactions between indoles and a series of carbonyl compounds at room temperature are described, which afford bis(indolyl)methanes with isolated yields up to 96%,
关键词 bis(indolylmethanes BF3.Et2O lndoles ALDEHYDES KETONES
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Highly Efficient Synthesis of Bis(indolyl)methanes Catalyzed by Sodium Tetrafluoroborate 被引量:2
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作者 KAMBLE, Vinod Tribhuvannathji BANDGAR, Babasaheb Pandurang BAVIKAR, Sudhir Narayanrao 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第1期13-15,共3页
Sodium tetrafluoroborate (NaBF4) was found to catalyze the electrophilic substitution reactions of indoles with aldehydes and ketones under solvent-free conditions to afford the corresponding bis(indolyl)methanes ... Sodium tetrafluoroborate (NaBF4) was found to catalyze the electrophilic substitution reactions of indoles with aldehydes and ketones under solvent-free conditions to afford the corresponding bis(indolyl)methanes in high yields. 展开更多
关键词 sodium tetrafluoroborate INDOLE ALDEHYDE KETONE bis(indolylmethane
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