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1.
L. Gomes de Lima M. Cariou H. Scordia R. Kergoat M. M. Kubicki J. E. Guerchais 《Journal of organometallic chemistry》1985,290(3):321-327
A new class of cyclic telluronium salts has been prepared. All the salts are stable in solution in CHCl3 or dimethylsulphoxide (DMSO). Conductivity measurements in DMSO and dimethylformamide (DMF) have shown that considerable ion pairing occurs in solution. Infrared, 1H, 13C, 125Te NMR, and mass spectra are reported and discussed. 相似文献
2.
A. Cosme M. S. Arias E. Glvez C. Ruano C. Ruano 《Journal of heterocyclic chemistry》1990,27(5):1457-1466
A series of 3 -aryl -3 -hydroxy-N -(4 ′-aryloxobutyl)quinuclidinium salts have been synthesized. The 1H nmr, 13C nmr and mass spectra of these compounds are described and discussed. 相似文献
3.
Dr. Goutam Kumar Kole Dr. Julia Merz Dr. Anissa Amar Dr. Bruno Fontaine Dr. Abdou Boucekkine Dr. Jörn Nitsch Sabine Lorenzen Dr. Alexandra Friedrich Dr. Ivo Krummenacher Marta Košćak Prof. Dr. Holger Braunschweig Prof. Dr. Ivo Piantanida Prof. Dr. Jean-François Halet Prof. Dr. Klaus Müller-Buschbaum Prof. Dr. Todd B. Marder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(8):2837-2853
Two N-methylpyridinium compounds and analogous N-protonated salts of 2- and 2,7-substituted 4-pyridyl-pyrene compounds were synthesised and their crystal structures, photophysical properties both in solution and in the solid state, electrochemical and spectroelectrochemical properties were studied. Upon methylation or protonation, the emission maxima are significantly bathochromically shifted compared to the neutral compounds, although the absorption maxima remain almost unchanged. As a result, the cationic compounds show very large apparent Stokes shifts of up to 7200 cm−1. The N-methylpyridinium compounds have a single reduction at ca. −1.5 V vs. Fc/Fc+ in MeCN. While the reduction process was reversible for the 2,7-disubstituted compound, it was irreversible for the mono-substituted one. Experimental findings are complemented by DFT and TD-DFT calculations. Furthermore, the N-methylpyridinium compounds show strong interactions with calf thymus (ct)-DNA, presumably by intercalation, which paves the way for further applications of these multi-functional compounds as potential DNA-bioactive agents. 相似文献
4.
Gui-Xiang Fu Zhang-Lin Zhou Lu Yu Yao-Zeng Huang 《Journal of mass spectrometry : JMS》1992,27(6):695-698
The fast atom bombardment (FAB) mass spectra of telluronium salts were studied. The spectra exhibit the intact cation (C+) and cluster ions ([M + C]+). The principal fragment ions in the FAB mass spectra of telluronium salts are [RTe]+, [R2Te]+˙, [R2Te − H]+, [RTeR′]+˙, and [RTeR′ + H]+. When the anion was [BPh4]−, interesting cluster ions such as [M + C − BPh3]+ appeared. 相似文献
5.
Elena K. Badeeva Elena V. Platova Elvira S. Batyeva Lidiya I. Kursheva Elena E. Zvereva Aleksander. E. Vandyukov Sergey A. Katsyuba Valeryi I. Kovalenko Oleg G. Sinyashin 《Heteroatom Chemistry》2011,22(1):24-30
New octathiotetraphosphetane ammonium salts are obtained based on the reaction of white phosphorus (P4) and elemental sulfur with aliphatic mercaptans in the presence of amines (morpholine , methylmorpholine, pyrrolidine, and N,N‐dimethylbenzylamine). Both the salts and novel Cu(I) chloride complex with the pyperidinium salt of octathiotetraphosphetane are characterized by IR/Raman spectroscopy in combination with DFT methods. The comparative spectral analysis reveals clear spectral features, characteristic for a P4S84− anion, which are present in IR and Raman spectra of all the compounds obtained. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 22:24–30, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20651 相似文献
6.
Liquid Nickel Salts: Synthesis,Crystal Structure Determination,and Electrochemical Synthesis of Nickel Nanoparticles
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Jeroen Sniekers Ken Verguts Dr. Neil R. Brooks Dr. Stijn Schaltin Dr. Thanh Hai Phan Dr. Thi Mien Trung Huynh Prof. Luc Van Meervelt Prof. Steven De Feyter Prof. Jin Won Seo Prof. Jan Fransaer Prof. Koen Binnemans 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):1010-1020
New nickel‐containing ionic liquids were synthesized, characterized and their electrochemistry was investigated. In addition, a mechanism for the electrochemical synthesis of nanoparticles from these compounds is proposed. In these so‐called liquid metal salts, the nickel(II) cation is octahedrally coordinated by six N‐alkylimidazole ligands. The different counter anions that were used are bis(trifluoromethanesulfonyl)imide (Tf2N?), trifluoromethanesulfonate (OTf?) and methanesulfonate (OMs?). Several different N‐alkylimidazoles were considered, with the alkyl sidechain ranging in length from methyl to dodecyl. The newly synthesized liquid metal salts were characterized by CHN analysis, FTIR, DSC, TGA and viscosity measurements. An odd‐even effect was observed for the melting temperatures and viscosities of the ionic liquids, with the complexes with an even number of carbon atoms in the alkyl chain of the imidazole having a higher melting temperature and a lower viscosity than the complexes with an odd number of carbons. The crystal structures of several of the nickel(II) complexes that are not liquid at room temperature were determined. The electrochemistry of the compounds with the lowest viscosities was investigated. The nickel(II) cation could be reduced but surprisingly no nickel deposits were obtained on the electrode. Instead, nickel nanoparticles were formed at 100 % selectivity, as confirmed by TEM. The magnetic properties of these nanoparticles were investigated by SQUID measurements. 相似文献
7.
The structural elucidation by NMR spectroscopy of trisubstituted α-pyridones and the isomeric 2-amino-γ-pyrones as well as their internal and external pyrylium salts is described. The most useful parameter for the differentiation between α-pyridones and isomeric γ-pyrones is the geminal coupling constant 2J(C-6, H-5) which changes from ~2.5 Hz to ~7 Hz whenever the cyclic amide group is replaced by an oxa-function; this applies to both the γ-pyrones and their pyrylium salts. The value of J(C-6, H-5) in the pyridones resembles that of the analogous coupling in N-vinylacetamide, whose sign determination by the selective population inversion (SPI) technique is reported. The 13C chemical shifts of seven pyridones, pyrones and pyrylium salts are reported and their structural correlations are discussed. Quick structural assignments in these classes of compounds may also be performed by evaluating the 14N chemical shifts, which often are accessible by the {14N}—1H-INDOR technique. The proton coupled 13C NMR spectra of two tetrasubstituted pyridines are also reported, and empirical correlations between long range C? H coupling constants and substituent electronegativity are discussed. 相似文献
8.
How‐Ghee Ang Wolfgang Fraenk Konstantin Karaghiosoff Thomas M. Klaptke Heinrich Nth Joanna Sprott Max Suter Martin Vogt Marcus Warchhold 《无机化学与普通化学杂志》2002,628(13):2901-2906
Urotropinium nitrate, N‐methylurotropinium azide, dinitramide and azotetrazolate salts have been prepared and fully characterized by analytical and spectoscopic (1H, 13C, 14N NMR, IR, Raman) methods. The structures of all four compounds have been determined using X‐ray diffraction techniques and represent new examples of the class of high energy density materials (HEDMs). 相似文献
9.
Daniel E. Lynch Ravinder Hayer Samantha Beddows Joy Howdle C. Douglas Thake 《Journal of heterocyclic chemistry》2006,43(1):191-197
10.
Neha Patel Minhajul Arfeen Tejender Singh Shweta Bhagat Ajay Sakhare Prasad V. Bharatam 《Journal of computational chemistry》2020,41(31):2624-2633
Nitreones are compounds with oxidation state 1 at the nitrogen, these compounds carry formal positive charge as well as two lone pairs of electrons at nitrogen center. These compounds are also known as divalent NI compounds and can be represented with the general formula L → N+ ← L, where L is an electron donating ligand. In the recent past, several divalent NI compounds have been reported with L = N-heterocyclic carbene (NHC), remote N-heterocyclic carbene (rNHC), carbocyclic carbene (CCC) and diaminocarbene. Recently, our group reported that a novel six-membered CCC (cyclohexa-2,5-diene-4-[diaminomethynyl]-1-ylidene) can stabilize N+ center in nitreones. As an independent carbene, this species is very unstable. In this work, modulation of this CCC using (a) annulation, (b) heterocyclic ring modification, (c) substitutions adjacent to the carbenic carbon, (d) exocyclic double bond insertion and (e) ring contraction, has been reported. These modulations and quantum chemical analyses helped in the identification of five new six-membered CCCs which carry improved donation and stability properties. Further, these CCCs were employed in the design of new divalent NI compounds (nitreones) which carry coordination bonds between ligands and N+ center. The molecular and electronic structure properties, and the donor→acceptor coordination interactions present in the resultant low oxidation state divalent NI compounds have been explored. 相似文献
11.
2,5-Quinonemethides of 1,6-Methano[10]annulene with the Structures of S,N- and N,N-Acylketene Acetals Investigation on the chemical reactivities of 2-(tert -butoxy)-1,6-methano[10]annulene and the syntheses of the compounds 2, 4, 6–8, 11, 13–22 are described; the results of 1H- and 13C-NMR-spectroscopic measurements are reported. 相似文献
12.
The synthesis and characterisation of a homologous series of monodentate benzimidazolium salts, 1–4 and their mononuclear silver(I)–NHC (where NHC = N-heterocyclic carbene) complexes, 5–8, are reported. The benzimidazolium salts were prepared from the N-alkylation of 1-methyl-benzimidazole with alkyl halides of varying carbon chain lengths. The mono silver(I)-NHC complexes, 5–8, were prepared by the reaction of the benzimidazolium salts with Ag2O. All the synthesised compounds were fully characterised by 1H-nuclear magnetic resonance (1H-NMR), 13C-NMR and fourier-transform infrared (FTIR) spectroscopy. The molecular structures of compounds 3·PF6, 4·PF6, 7 and 8 were elucidated through single-crystal X-ray diffraction analyses. We postulate that the attachment of long alkyl chains to the heterocyclic core of 1-methyl benzimidazole could induce mesophase formation. The liquid crystalline behaviour of the benzimidazolium salts was investigated by polarised optical microscope and differential scanning calorimetry. Salts 3 and 4 were found to be thermotropic liquid crystals which exhibited a smectic A phase. However, upon complexation with silver(I) ions, all the Ag(I)–NHC complexes are found to be non-mesogenic. 相似文献
13.
Preparation and Structures of 2‐Substituted 5‐Benzyl‐3‐methylimidazolidin‐4‐one‐Derived Iminium Salts,Reactive Intermediates in Organocatalytic Transformations Involving α,β‐Unsaturated Aldehydes
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Uroš Grošelj Albert Beck W. Bernd Schweizer Dieter Seebach 《Helvetica chimica acta》2014,97(6):751-796
Preparations of the title compounds, 5 – 7 (Scheme 1 and Table 1), of their ammonium salts, 9 – 11 (Scheme 2 and Table 2), and of the corresponding cinnamaldehyde‐derived iminium salts 12 – 14 (Scheme 3 and Table 3) are reported. The X‐ray crystal structures of 15 cinnamyliminium PF6 salts have been determined (Table 4). Selected 1H‐NMR data (Table 5) of the ammonium and iminium salts are discussed, and structures in solution are compared with those in the solid state. 相似文献
14.
Kartar S. Arora C. G. Overberger 《Journal of polymer science. Part A, Polymer chemistry》1986,24(3):511-524
The synthesis of N,N-diethyl-9-carbazolylacetamide ( 6 ), (R,S)- and (R)-N,N-diethyl-2-(9-carbazolyl)propanamide ( 7 ), N,N′-dimethyl-N,N′-di-(9-carbazolylacetyl)-1,2-ethanediamine ( 11 ), and (R)-N,N′-dimethyl-N,N′-di[2-(9-carbazolyl)propanoyl]-1,2-ethanediamine ( 13 ) is reported. The racemic compound, (R,S)-2-(9-carbazolyl)propanoic acid ( 2 ), was resolved by partial crystallization of the diastereomeric salts formed between 2 and (+)-α-methylbenzylamine. The 1H-NMR spectra of 6 and 7 showed magnetic nonequivalence of the chemically equivalent protons of the methyl and methylene groups in 6 and 7 due to partial double bond character of the amide bond. The upfield resonances corresponding to the two sets of methyl and methylene protons were assigned by the aromatic solvent-induced shift (ASIS) method to the protons anti to the carbonyl oxygen in the conformation of amide bond in 6 and 7 . The 1H-NMR spectra of 11 and (R)- 13 were used to determine the population of anti-anti, anti-syn (syn-anti) and syn-syn conformers in the structures of these dimer model compounds; the relative conformer populations were 0.45:0.47:0.08 and 0.28±0.02:0.29±0.01:0.43±0.01 in 11 and (R)- 13 . 相似文献
15.
Thomas M. Klaptke Burkhard Krumm Matthias Scherr 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(1):m17-m19
The title compounds, diaquadinitramidatolithium(I), [Li(N3O4)(H2O)2], (I), and pyridinium dinitramidate, C5H6N+·N3O4−, (II), differ significantly in their cation–anion contacts. The Li+ atom of (I) is coordinated by two O atoms of the dinitramide anion in a chelate and by four additional water molecules, with the Li and central N atom of the anion on a twofold rotation axis. The pyridinium cation of (II) exhibits a contact with the dinitramide anion via an intermolecular N—H...N hydrogen bridge. These interactions are compared with those found in reported anhydrous lithium dinitramide and ammonium dinitramide salts. 相似文献
16.
Grazia Bencivenni Dr. Diana Salazar Illera Dr. Maria Moccia Prof. K. N. Houk Dr. Joseph A. Izzo Dr. Johanna Novacek Prof. Paolo Grieco Prof. Mathew J. Vetticatt Prof. Mario Waser Prof. Mauro F. A. Adamo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(44):11352-11366
Chiral phase-transfer catalysis provides high level of enantiocontrol, however no experimental data showed the interaction of catalysts and substrates. 1H NMR titration was carried out on Cinchona and Maruoka ammonium bromides vs. nitro, carbonyl, heterocycles, and N−F containing compounds. It was found that neutral organic species and quaternary ammonium salts interacted via an ensemble of catalyst +N−C−H and (sp2)C−H, specific for each substrate studied. The correspondent BArF salts interacted with carbonyls via a diverse set of +N−C−H and (sp2)C−H compared to bromides. This data suggests that BArF ammonium salts may display a different enantioselectivity profile. Although not providing quantitative data for the affinity constants, the data reported proofs that chiral ammonium salts coordinate with substrates, prior to transition state, through specific C−H positions in their structures, providing a new rational to rationalize the origin of enantioselectivity in their catalyses. 相似文献
17.
Lixuan Liang Dr. Kai Wang Chengming Bian Liming Ling Prof. Zhiming Zhou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(44):14902-14910
A series of new energetic salts based on 4‐nitro‐3‐(5‐tetrazole)furoxan (HTNF) has been synthesized. All of the salts have been fully characterized by nuclear magnetic resonance (1H and 13C), infrared (IR) spectroscopy, elemental analysis, and differential scanning calorimetry (DSC). The crystal structures of neutral HTNF ( 3 ) and its ammonium ( 4 ) and N‐carbamoylguanidinium salts ( 9 ) have been determined by single‐crystal X‐ray diffraction analysis. The densities of 3 and its nine salts were found to range from 1.63 to 1.84 g cm?3. Impact sensitivities have been determined by hammer tests, and the results ranged from 2 J (very sensitive) to >40 J (insensitive). Theoretical performance calculations (Gaussian 03 and EXPLO 5.05) provided detonation pressures and velocities for the ionic compounds 4 – 12 in the ranges 25.5–36.2 GPa and 7934–8919 m s?1, respectively, which make them competitive energetic materials. 相似文献
18.
Dušan J. Radanović Zoran D. Matović Gustavo Ponticelli Paola Scano Inessa A. Efimenko 《Transition Metal Chemistry》1994,19(6):646-650
Summary The synthesis and characterization of AuIII complexes with several heterocyclic ligands are reported. The compounds have general formula [AuX3(L)], where L =N-methylimidazole (N-MeIz),N-ethylimidazole (N-EtIz),N-propylimidazole (N-PrIz), benzoxazole (BO), 2-methylbenzoxazole (2-MeBO), 2,5-dimethylbenzoxazole (2,5-diMeBO), 2-amino-pyrimidine (2-APm), 4(6) -hydroxy-pyrimidine [4(6)-hydrPm] or hypoxanthine (Hypox) and X = Cl or Br. Elemental analysis, conductivity measurements and spectral studies were used for the characterization of the complexes. A square-planar geometry withN-bonded heterocyclic ligands is suggested. 相似文献
19.
Jolanta Jaroszewska Iwona Wawer Janusz Oszczapowicz 《Magnetic resonance in chemistry : MRC》1984,22(5):323-327
13C and 1H chemical shifts of fourteen N-alkylmethylquinolinium salts in DMSO-d6 are reported, and compared with those of the eleven corresponding methylquinoline bases. The influence of ring substitution by methyl groups in the salts and substitution at the nitrogen atom and the effect of the anion are discussed. 相似文献
20.
Masahiro Suzuki Mariko Yumoto Mutsumi Kimura Hirofusa Shirai Kenji Hanabusa 《Helvetica chimica acta》2004,87(1):1-10
The new L ‐lysine alkali‐metal salts 1 – 5 (M+=Na+ and K+) with different alkyl groups at the Nα‐position were easily synthesized, and their hydro‐ and organogelation properties were investigated. All compounds were H2O‐soluble, and some salts, especially the potassium salts, functioned as a hydrogenator that could gel water below 2 wt‐%. These salts also had organogelation abilities for many organic solvents. 相似文献