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1.
《Green Chemistry Letters and Reviews》2013,6(4):289-310
Abstract The present overview describes ionic liquids as alternate, attractive solvents of today and tomorrow in organic synthesis. Since this subject is too wide and developments have been too fast, only a recent account is presented on indispensable carbon-carbon bond forming named reactions such as Knoevenagel, Michael Aldol, Biginelli Reaction, and so on, which has never been done before exclusively. 相似文献
2.
AbstractA three-component Strecker-type reactions was applied for the synthesis of benzofuran derivatives through the reaction of 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone (euparin), primary amines and trimethylsilyl cyanide (TMSCN) in the presence of catalytic amount of ZnO-nanorods (ZnO-NR) and piperidine in acetonitrile at room temperature. The method has proved to be synthetically simple, and effective with high atom economy and yield. The catalyst also revealed significant reusability. Moreover, the antioxidant activity and free radical scavenging capacity of the newly synthesized such as 4a, 4c, 6a and 6c was screened using free radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays and compared with hydroxytoluene (BHT) and tert-butylhydroquinone (TBHQ). These compounds exhibit good DPPH radical scavenging and ferric reducing antioxidant power (FRAP) assays. 相似文献
3.
Hossein Reza Darabi Ali Reza Mohebbi Mohammad Bolourtchian 《Supramolecular chemistry》2013,25(6):465-468
The synthesis, properties and energy-optimized structure of stilbenophanes 1a–3a are reported. 1H NMR spectroscopy of 1a shows it contains vinylic protons (unlike larger stilbenophanes), which appear as two doublets showing its unexpected configuration. Protons of the methylene bridge of 1b are also observed at different chemical shift, showing that they are diastereomeric protons. It is also found that the stereochemical outcome of the intramolecular McMurry reaction is strongly influenced by the length of the alkyl bridge. 相似文献
4.
G. Göndös L. Gera G. Dombi G. Bernáth 《Monatshefte für Chemie / Chemical Monthly》1996,127(11):1167-1171
Summary In contrast to their aromatic analogues, the corresponding saturated diamides5–9 are formed exclusively when hexahydro-3,1,4-benzoxazinones (3,4) are reacted with amines. The cyclodehydration reaction of the diamides5–9 cannot be carried out at arbitrarily high temperatures.Saturated Heterocycles, Part 217. Part 216: L. Simon, S. G. Talpas, F. Fülöp, G. Bernáth, G. Argay, A. Kálmán, P. Sohár (1995) J Heterocyclic Chem32: 161 相似文献
5.
Rohani Prasad Burman Shantanu Gupta Jyoti Bhatti Krishan Verma Devendra Rajak 《Natural product research》2019,33(8):1147-1157
First total synthesis of carpatamide-A 7a, cytotoxic arylamine derivative isolated from marine derived Streptomyces sp., was achieved in twelve steps with overall yield of 24% with seven longest linear steps. In the penultimate step, dienoic acid 13 and an amino-phenylpropionic acid methyl ester core 21 were coupled to synthesize methylated derivativative of carpatamide-A 22 followed by demethylation of the intermediate with BBr3 to accomplish carpatamide-A 7a. Both precursors 13 and 21 were synthesized from readily available starting materials i.e. isovaleraldehyde 8 and 2, 4-dihydroxy benzaldehyde 14. 相似文献
6.
Orhan Altan Osman Serindağ Koray Sayın Duran Karakaş 《Phosphorus, sulfur, and silicon and the related elements》2016,191(7):993-999
Novel phosphine oxides, (((3-methylpyridin-2-yl)amino)methyl)diphenylphosphine oxide (1) and diphenyl((pyrazin-2-ylamino)methyl)phosphine oxide (2), were synthesized and characterized. Phosphines ligands (3 and 4) were obtained by the reduction of 1 and 2 with AlH3, monitored by 31P NMR spectroscopy. Pd(II) complexes of 3 and 4 were synthesized and characterized (5 and 6). The catalytic activity of 5 and 6 was tested on the reaction of styrene with both activated and deactivated aryl bromides in air. The results of the catalytic experiments were discussed through DFT calculations. 相似文献
7.
Mavallur Varalakshmi Chamarthi Nagaraju Palaa Krishna 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):853-857
AbstractA series of new class of diethyl N-2-hydroxyethyl-N'-substituted phosphoramidimidates 6(a–e) and diethyl P-morpholino-N-substituted phosphonimidates 6(f–j) was synthesized. The precursor intermediates, diethyl substituted phosphoramidites 3(a–b) were prepared initially by a reaction of various amines 1(a–b) and diethyl phosphorochloridite (2) and then they were treated by in situ with aromatic/alkyl azides through Staudinger reaction to accomplish title products. Structures of all the synthesized compounds were characterized by spectroscopic data such as IR, NMR (1H, 13C, 31P), mass, and elemental analyses. The synthesized compounds were screened for their in vitro antimicrobial activity to understand their biological potency. The biological screening results disclosed that compounds 6b, 6c, 6e, 6g, 6h and 6j having potent antimicrobial activity against all the tested pathogens. 相似文献
8.
《Journal of Coordination Chemistry》2012,65(13):2105-2112
A one-dimensional linear chain polymer {[Mn(OOCC6H4Fc)2(μ 2-OH2)(DMF)2]} n (1) was obtained by substitution from a precursor polymer {[Mn(OOCC6H4Fc)2(μ 2-OH2)(H2O)2](H2O)} n (P1), in which the terminal coordinated H2O molecules are substituted by DMF, while the bridging aqua molecules are intact, so product 1 and precursor P1 are isomorphous. Polymer 1 behaves as a 1D Heisenberg Mn(II) chain with weak intrachain antiferromagnetic interaction between the local high-spin Mn(II) ions; the exchange coupling parameters J = ?5.00 cm?1 are larger than most of the reported di-Mn(II) complexes containing μ 2-aqua and μ 2-carboxylato units and some one-dimensional Mn(II) carboxylic polymers. 相似文献
9.
《Journal of Coordination Chemistry》2012,65(7):1153-1164
Two complexes, [Zn2L(µ-OAc)](ClO4) (1) and [Mn2L(OAc)2]?·?4H2O (2), were synthesized by [2?+?2] cyclo-condensation between 2,6-diformyl-4-fluorophenol and 1,3-propyldiamine in the presence of metal ions M(II) (M?=?Zn and Mn), and were characterized by chemical analyses, IR spectra, electrospray mass spectra, and X-ray determinations. The results show that 1 forms dimers through hydrogen bonding. In 2, lattice waters, forming a 1-D water chain, function as glue to form a 3-D supramolecular network through extended hydrogen bonding. pBR322 plasmid DNA can be transformed to nicked form in air by 1 or nicked and linear forms in air by 2. Moreover, their antibacterial activities against S. aureus were investigated using penicillin as reference system. 相似文献
10.
Stephen D. Pastor Ramanathan Ravichandran Paul A. Odorisio Edward T. Hessell 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):117-123
Abstract The reaction of the arenethiols 4a-b with formaldehyde and the sec-amines 5a-c gave the aminomethyl aryl sulfides 6a-d. The reaction of the hemimercaptals 3a-b with 5a in methanol gave 6a-b in high yield. In acetonitrile reaction media, 6b was obtained by the reaction of 3b with 5a which suggested that 7b was not an intermediate in the formation of 6b in methanolic media. The absence of 7b in methanolic media suggests that the methylenesulfonium ion 8b is not an reaction intermediate. The formation of 7b was observed in the reaction of 3b with methanol when catalyzed by the Lewis acid tetrafluoroboric acid diethyl ether complex. The experimental observations are best explained by a mechanism whereby 3a-b are in rapid equilibrium with 4a-b under the basic reaction conditions. Rapid reaction of the liberated formaldehyde with 5a leads to the normal Mannich reaction pathway. Consistent with this mechanism, the reaction of a mixture of 3a-b and 12 with 5a gave both 6a-b and 13. 相似文献
11.
Sophie Danappe Fabien Boeda Christian Alexandre Anne‐Marie Aubertin Nathalie Bourgougnon 《合成通讯》2013,43(21):3225-3239
Synthesis of eight nucleoside analogues 4–11 with a methylenecyclobutane unit is described. Wittig reaction with 2‐hydroxymethylcyclobutanone 12 gave a mixture of Z (13) and E (14) derivatives, which was separated before functional modifications. The heterocyclic moieties were introduced via a Mitsunobu reaction either on the saturated chain or on the unsaturated chain. When adenine was used in this reaction, only the N‐9 substitution products were obtained. Removal of the protecting groups provided the target products. 相似文献
12.
Kazem Karami Mahboubeh Hosseini-Kharat Zahra Shirani-Sarmazeh Reza Zahedi-Nasab Corrado Rizzoli Janusz Lipkowski 《Journal of Coordination Chemistry》2016,69(5):763-778
Six secondary amine palladacycles bearing monodentate ligands (1a, 2a), 1,2-bis(diphenylphosphino)ethane (dppe) and 1,3-bis(diphenylphosphino)propane (dppp) containing bridging and bidentate ligands (1b, 2b–d), and four C,C-type phosphorus ylide complexes containing thiourea (tu) (3a), phenyl isothiocyanate (4a), and bridging and terminal azide groups (5 and 5a) have been synthesized. Resulting complexes have been characterized by elemental analyses, IR, 1H-, 13C{1H}-, and 31P{1H}-NMR spectroscopy with single crystal X-ray structure determination of 1a and 2a. The Pd in 1a and 2a occupies the center of a slightly distorted square planar environment formed by Caryl, Namine, Npyridine, and Cl. The catalytic efficiency of complexes showed that in most cases, amine palladacycles display better catalytic activities than the phosphorus ylide Pd(II) complexes. Comparison between bidentate and bridging dppe complexes showed that dppe-bridged dimer 2d has higher catalytic activity than dppe bidentate complex. 相似文献
13.
1,3-Disubstituted hexahydropyrimidin-5-yl(phenyl)methanone (products 1–5) were prepared from the reaction of dibenzoylmethane with primary amines and formaldehyde in the presence of Lewis acid catalyst at ambient temperature. Replication of the reaction with acetylacetone and ethyl aetoacetate yielded 1,1′-(1,3-disubstituted hexahydropyrimidine-5,5-diyl)diethanone (products 6–10) and ethyl 5-acetylhexahydropyrimidine-5-carboxylate (products 11–13), respectively. Yields obtained ranged from 69 to 89%. 相似文献
14.
Johannes Reisch Akkinepalli Raghu Ram Rao Cyril Odianose Usifoh 《Monatshefte für Chemie / Chemical Monthly》1994,125(1):79-83
Summary The reaction of theophylline (1) with 2-methyl-3-butyn-2-ol and 1-butyn-3-ol under Mitsunobu conditions gave the respective 9-substituted derivatives 9-[2-(2-methyl-3-butynyl)]-theophylline (2) and 9-[2-(3-butynyl)]-theophylline (3). On reaction with 2-methyl-3-buten-2-ol, theophylline yielded in addition to the 9-[2-(2-methyl-3-butenyl)]-theophylline (4), two more cyclic products, identified as 1,5,5a,8-tetrahydro-1,3,8,8-tetramethyl-2H-pyrrolo[1,2-e]purine-2,4(3H)-dione (5) and 8a,9-dihydro-1,3,6,6-tetramethyl-1H-pyrrolo[2,1-f]purine-2,4(3H,6H)-dione (7).
Acetylenchemie, 32. Mitt.: Alkinylierung und cyclische Umlagerung von Theophyllin mit ungesättigten Alkoholen mittels Mitsunobu-Reaktion
Zusammenfassung Die Reaktion von Theophyllin (1) mit 2-Methyl-3-butin-2-ol und 1-Butin-2-ol unter Mitsunobu-Bedingungen führte zu den 9-substituierten Derivaten 9-[2-(2-Methyl-3-butinyl)]-theophyllin (2) bzw. 9-[2-(3-Butinyl)]-theophyllin (3). Bei der Reaktion mit 2-Methyl-3-buten-2-ol ergab Theophyllin außer 9-[2-(2-Methyl-3-butenyl)]-theophyllin (4) noch zwei weitere cyclisierte Produkte, die als 1,3,8,8-Tetramethyl-1,5,5a,8-tetrahydro-pyrrolo[1,2-e]purin-2,4(3H)-dion (5) und 1,3,6,6-Tetramethyl-8a,9-dihydro-1H,6H-pyrrolo[2,1-f]purin-2,4-dion (7) identifiziert wurden.相似文献
15.
L. Boubakri L. Mansour A. H. Harrath I. Özdemir 《Journal of Coordination Chemistry》2018,71(2):183-199
A novel series of N-heterocyclic carbene-phosphine palladium(II) complexes has been synthesized and fully characterized by IR, 1H NMR, 13C NMR, and 31P NMR spectroscopies, and elemental analysis. The new N-heterocyclic carbene (NHC)-phosphine palladium(II) complexes 3a–h have been easily prepared by the reaction of the corresponding PEPPSI (pyridine-enhanced precatalyst preparation stabilization and initiation) complexes 2a–h and triphenylphosphine in dichloromethane in high yields. These complexes were applied as catalyst precursors which efficiently catalyzed Sonogashira reactions between aryl bromides and phenylacetylene to afford the corresponding products in good yields. The bulky NHC-Pd-PPh3 complexes 3 were tested against Gram-positive and Gram-negative bacteria to study their biological activity. All the complexes exhibit antibacterial against these organisms. Investigation of the anti-acetylcholinesterase activity of the studied complexes showed that compounds 3a and 3b exhibited moderate activity at 100 μg mL?1 and product 3b is the most active. 相似文献
16.
2,5-bis-(4-biphenyl)-yl-1,3,4-oxadiazole (1a), 2,5-bis-(4-(6,8-difluoro)-biphenyl)-yl-1,3,4-oxadiazole (1b) and 2,5-bis-(4-(spiro-fluorenyl)-phenyl)-yl-1,3,4-oxadiazole (1c) were designed, synthesized and characterized. 1a–c were easily obtained from Suzuki reactions between 2,5-bis-(4-bromo-phynyl)-[1,3,4]oxadiazole (2) and aromatic boronic acids (3). They were characterized by 1H-NMR, DSC, TGA, UV-Vis, photoluminescence (PL) spectrometry and CV. The melting temperatures (T
m
) of 1a–c are 237, 208 and 370 °C, respectively, much higher than that of 2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazole (PBD, T
m
= 136 °C). The oxidation potentials of 1a–c are 1.86, 1.94 and 1.18 V, and their reduction potentials are −2.31, −2.22 and −2.27 V, respectively, indicating that the
introduction of electronegative oxadiazole unit lowers the electron density in molecules and enhances their stabilities. The
LUMO/HOMO energy levels of 1a–c are as low as −2.39/−6.56, −2.48/−6.69 and −2.43/−5.88 eV, respectively. The good thermal stabilities and low orbital levels
of 1a–c make them promising electron-transporting or hole-blocking materials for organic optoelectronic devices. 相似文献
17.
Wolfgang Dostal Gottfried Heinisch Gerhard Lötsch 《Monatshefte für Chemie / Chemical Monthly》1988,119(6-7):751-759
Procedures for the preparation of the novel tricyclic ketones 10,11-dihydro-5H-benzo[4,5]cyclohepta[1,2—d]pyridazin-5-one (3), 5,6-dihydro-11H-benzo[4,5]cyclohepta[2,1—c]pyridazin-11-one (4), and 10,11-dihydro-5H-benzo[4,5]-cyclohepta[1,2—c]pyridazin-5-one (5) starting from a preformed 1,2-diazine system are proposed. The key intermediates7,19, and11 are prepared from (2-phenylethyl)pyridazines6 and18 by introduction of a carboxylic functionality via homolytic alkoxycarbonylation or via a sulfonylReissert-type reaction.
Zur Chemie von Pyridazinen, 36. Mitt.: Neuartige Diazaanaloga des 10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ons
Zusammenfassung Methoden zur Darstellung der neuen trizyklischen Ketone 10,11-Dihydro-5H-benzo[4,5]cyclohepta[1,2—d]pyridazine-5-on (3), 5,6-Dihydro-11H-benzo[4,5]cyclohepta[2,1—c]pyridazin-11-on (4) und 10,11-Dihydro-5H-benzo[4,5]cyclohepta[1,2—c]pyridazin-5-on (5) ausgehend von einem präformierten 1,2-Diazinsystem werden vorgeschlagen. Die Schlüsselbausteine dieser Synthesen7,19 und11 werden durch Einführung einer Carboxylfunktion in die (2-Phenylethyl)pyridazine6 und18 über homolytische Alkoxycarbonylierung bzw. eine Sulfonyl-Reissert-Reaktion erhalten.相似文献
18.
A novel 6-acetylpyridine-2-carboxylic acid (4) was obtained occasionally during the synthesis of asymmetric ethyl 6-acetylpyridine-2-carboxylate (3) from 2,6-dipiclinic acid (1). Compounds 3 and 4 could transform mutually under some specific conditions. Two reactions of distinctive types occurred when they reacted with the aromatic amines as precursors, due to different functional groups on the 2-position of pyridine in the molecules of 3 and 4: one was Schiff base condensation and the other was an amidation reaction. From the latter reaction, two series of new compounds, pyridine carboxamides (5a–d) and pyridine tert-carboximides (6a–h), resulted. The relevant reaction mechanism is discussed in detail. 相似文献
19.
20.
Francisco Ramón Fortea-Pérez Giovanni De Munno 《Journal of Coordination Chemistry》2014,67(23-24):4003-4015
New bis(oxamato)palladate(II) complexes, [Pd(H2O)4][Pd(2,6-Me2pma)2]·2H2O (1), (n-Bu4N)2[Pd(2,6-Me2pma)2]·2H2O (2a), and (n-Bu4N)2[Pd(2,6-Me2pma)2]·2CHCl3 (2b) (2,6-Me2pma = N-2,6-dimethylphenyoxamate and n-Bu4N+ = tetra-n-butylammonium), have been synthesized and the structures of 1 and 2b characterized by single-crystal X-ray diffraction. Complex 1 is a double salt constituted by tetraaquapalladium(II) cations and bis(oxamato)palladate(II) anions interlinked by hydrogen bonds. The palladium(II) ions in 1 are four-coordinate with two oxygens and two nitrogens from two fully deprotonated oxamate ligands (anion), and four water molecules (cation) building centrosymmetric square-planar surroundings. Centrosymmetric bis(oxamato)palladate(II) anions occur in 2b as in 1, the charge balance in this compound being ensured by the bulky n-Bu4N+. The catalytic role of 1 and 2a for the Suzuki reaction has been investigated by using a series of aryl iodide/bromide derivatives in the conventional organic medium dimethylformamide. The tetraaquapalladium(II) unit in 1 appears to be active in the catalytic Suzuki cross-coupling reactions, but it readily decomposes to inactive palladium black. 相似文献