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1.
A proton is split out from the NH group of indole to give the anhydro bases in all cases when 4-(3-indolyl)pyridinium salts with alkyl, benzyl, phenacyl, and quinolylmethyl residues attached to the pyridinium nitrogen atom are treated with alkali.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1645–1647, December, 1981. 相似文献
2.
Satoshi Sakaguchi Miaki Kawakami Kyung Soo Yoo 《Journal of organometallic chemistry》2010,695(2):195-6791
The synthesis of a series of azolium salts such as azolium iodides and chlorides having both N-anionic functional group and N-alkyl group have been developed. Reaction of azolium iodides or chlorides with Ag2O gave the corresponding NHC-Ag complexes. It was found that the resulting NHC-Ag complexes derived from azolium iodides or chlorides differ in their physical properties. The azolium chlorides as well as azolium iodides were successfully converted into the NHC-Ag complexes, which subsequently reacted with PdCl2(CH3CN)2 to give the anionic amidate/NHC-Pd complexes. Thus, a variety of the NHC-Pd complexes could be obtained from benzimidazolium and imidazolium salts. 相似文献
3.
Hannah K. Box Tyler O. Howell William E. Kennon Griffin A. Burk Henry U. Valle T. Keith Hollis 《Tetrahedron》2017,73(16):2191-2195
The coupling of N-heterocyclic azoles (imidazoles, benzimidazoles, triazoles) to bromobenzenes (1,2-; 1,3-; or 1,4) in a step-wise, sequential manner was accomplished by manipulation of reaction time and stoichiometry, which provided straight-forward access to unsymmetrical bis(azolium) salts in only three isolation steps from commercially-available starting materials. Eight mono(azole) substituted bromobenzenes, four mono(azolium)bromobenzene salts, twelve unsymmetrical bis(azole)benzenes, and fourteen unsymmetrical bis(azolium) salts, which are precursors for pincer ligand complexes, are reported. 相似文献
4.
Ishai Sataty 《Magnetic resonance in chemistry : MRC》1971,3(4):429-432
The methylene protons of dibenzyl sulphoxide are magnetically equivalent in low dielectric and non-equivalent in high dielectric constant solvents, while for diphenacyl sulphoxide this behaviour is reversed. In both cases, the variation in the magnitude of the non-equivalence reflects a greater downfield shift of one methylene proton than the other on passing from non-polar to polar solvents. By contrast, the chemical shift difference between the benzyl methylene protons or between the phenacyl methylene protons of benzyl phenacyl sulphoxide varies only slightly with solvent polarity. 相似文献
5.
In order to reveal the possible formation of free N-heterocyclic carbene (NHC) in DMF-azolium and acetate solutions, the proton exchange equilibrium between azolium cations and CH3COO− was investigated (by cyclic voltammetry) by adding CH3COOH or tetrabutylammonium acetate to DMF solutions of imidazolium or thiazolium salts of different acidity.The voltammetric analysis confirms that the deprotonation of the azolium cation by CH3COO− (with the formation of free NHC) is significant in the case of the more acidic thiazolium cations, while it is not effective with the less acidic imidazolium ones.Accordingly, the NHC-catalyzed benzoin condensation was carried out in DMF solutions of azolium salts, tetrabutylammonium acetate, and benzaldehyde. Benzoin was isolated only starting from the more acidic thiazolium salts. 相似文献
6.
7.
Thomson JE Campbell CD Concellón C Duguet N Rix K Slawin AM Smith AD 《The Journal of organic chemistry》2008,73(7):2784-2791
Screening of a range of azolium salts, bases and solvents for reactivity indicates that triazolinylidenes, generated in situ with KHMDS in THF, promote the Steglich rearrangement of oxazolyl carbonates with high catalytic efficiency (typical reaction time 5 min at <1.5 mol % NHC). This protocol shows wide substrate applicability, even allowing the efficient generation of vicinal quaternary centers. An improved experimental procedure is also described that allows a simplified one-pot reaction protocol to be employed with similarly high catalytic efficiency. 相似文献
8.
Onium salts, namely sulfonium, phosphonium, ammonium, and pyridinium salts containing phenacyl group are photoinitiators appropriate for the polymerization of monomers such as oxiranes and vinyl ethers, which are not polymerizable by a free-radical mechanism. The initiation is accomplished by direct or indirect (sensitized) photolysis of the salts. Depending on the type of the salt, the direct photoinitiation of cationic polymerization involves reversible or irreversible processes. The photolysis of phenacylsulfonium compounds proceeds by a reversible process, while the other types undergo irreversible photolysis leading to complete fragmentation of the photoinitiator. An additionally useful tool, namely photosensitized generation of initiating species enlarges the versatility of these salts as photoinitiators. Photoinitiated free-radical and zwitterionic polymerizations by using phenacyl-type salts are also addressed. Keto-enol tautomerization of phenacyl pyridinium salts is discussed. Moreover, an interesting application concerning in situ synthesis of clay-poly(methyl methacrylate) nanocomposites with the aid of the phenacyl anilinium salt-based photopolymerization technique is noted. 相似文献
9.
One-pot synthesis of phenacyl esters from acetophenone, [Bmim]Br3, and potassium salts of carboxylic acids under solvent-free conditions gave the corresponding phenacyl esters with excellent yields. 相似文献
10.
Akimova T. I. Trofimenko N. N. Ivanenko Zh. A. 《Russian Journal of Organic Chemistry》2003,39(9):1346-1348
1-Substituted 3,5-diphenylpyrazinium salts were obtained by reactions of tertiary bis(phenacyl)amines with ammonium acetate, hydroxylamine hydrochloride, and hydrazine hydrate in acid medium. The reaction of quaternary dimethylbis(phenacyl)ammonium bromide with hydrazine hydrate afforded 3,6-diphenylpyridazine. 相似文献
11.
Baker MV Brown DH Heath CH Skelton BW White AH Williams CC 《The Journal of organic chemistry》2008,73(23):9340-9352
This paper describes the synthesis, structural characterization, and solution behavior of some xylyl-linked imidazolium and benzimidazolium cyclophanes decorated with alkyl or alkoxy groups. The addition of alkyl/alkoxy chains to the cyclophanes allows for studies in chlorinated solvents, whereas previous solution studies of azolium cyclophanes have generally required highly polar solvents. The azolium cyclophanes may exist in a syn/syn conformation (azolium rings mutually syn, arene rings mutually syn) or a syn/anti conformation (azolium rings mutually syn, arene rings mutually anti). The preferred conformation is significantly affected by (i) binding of bromide (ion pairing) to the protons on the imidazolium or benzimidazolium rings, which occurs in solutions of bromide salts of the cyclophanes in chlorinated solvents, and (ii) the addition of alkoxy groups to the benzimidazolium cyclophanes. These structural modifications have also led to cyclophanes that adopt conformations not previously identified for similar azolium cyclophane analogues. Detailed (1)H NMR studies for one cyclophane identified binding of bromide at two independent sites within the cyclophane. 相似文献
12.
13.
[reaction: see text]. A library of cycloimonium salts has been prepared through Westphal reaction in solid-phase. By reaction of solid-support-bound azolium or azinium acetates 2, 1,2-diketones 4, and base, cycloimonium salts 5 were synthesized in good to high yield and purities. 相似文献
14.
Chernoburova E. I. Lishchuk V. A. Ovchinnikov K. L. Kolobov A. V. Dzhafarov M. Kh. Vasilevich F. I. Zavarzin I. V. 《Russian Chemical Bulletin》2016,65(12):2965-2969
Russian Chemical Bulletin - A reaction of 5-O-succinoylavermectin B1 with alkylating agents, namely phenacyl halides, bromoacetanilides, and benzyl bromides, was studied. Esters of... 相似文献
15.
Benzyl chloride and phenacyl chloride are reported to condense with sodium acetate or sodium benzoate, affording the corresponding esters [1–4]. This suggested that a dichloride monomer can poly condense with a sodium dioate, affording a polyester. Akhmedzade and Yasnopolskii reported one such polyester synthesis based on polycondensation of p-xylylene dihalide with sodium terephthalate [5]. As phenacyl chloride is more reactive than benzyl chloride is more reactive than benzyl chloride [4], 4,4′-dichloroacetyldiphenyl ether (DADE) should prove even more reactive than a dichloride of the Ar(CH2Cl)2 type. The work presented here comprises a study of the polycondensation of DADE with sodium adipate (ADP), sebacate (SEB), or terephthalate (TER). 相似文献
16.
A. Kh. Gyul’nazaryan T. A. Sahakyan G. T. Sargsyan J. V. Grigoryan G. M. Muradyan A. M. Petrosyan G. A. Panosyan 《Russian Journal of General Chemistry》2016,86(9):2067-2070
Stevens rearrangement was studied of ammonium salts where piperidinium or morpholinium groups are linked to prop-2-yn-1-yl moiety and labile hydrogen atom functions (methoxycarbonylmethyl, phenacyl, cyanomethyl). In the case of phenacyl analog furan derivatives were formed, in other cases dienamines were the reaction products. 相似文献
17.
Several acidic azolium salts prepared from oxazole, thiazole, and imidazole derivatives were investigated as catalysts in N-glycosylation reaction using a silylated modified pyrimidine and an acylated ribose or glucose to afford the corresponding pyrimidine nucleoside. Among the salts, 2-methyl-5-phenylbenzoxazolium perchlorate showed the highest catalytic activity. This salt is a nonhygroscopic crystalline compound that shows higher activity than the frequently used trimethylsilyl triflate. Reactions with this salt can be conducted in gram scales. 相似文献
18.
《Tetrahedron letters》1988,29(4):491-492
A facile entry into the almost unknown azolium azolate inner salts is described, and the structure of these highly dipolar compounds is well reflected by their spectroscopic properties and reactivity towards electrophiles (MeI) and dipolarophiles (DMAD) under mild conditions. 相似文献
19.
《Mendeleev Communications》2023,33(2):180-183
A simple one-step synthesis of (NHC)2NiCl2 complexes containing bulky N-heterocyclic carbene (NHC) ligands relies on the C–H metallation of N,N'-diaryl-substituted azolium salts, NHC-precursors, with NiCl2Py2 in the presence of Cs2CO3 and pyridine. This procedure allows one to implement all synthetic manipulations in air. 相似文献
20.
L. M. Potikha A. R. Turelyk V. A. Kovtunenko A. V. Turov G. V. Palamarchuk R. I. Zubatyuk O. V. Shishkin 《Chemistry of Heterocyclic Compounds》2010,46(6):742-753
(Z)-4-Bromo-1,3-di(2-thienyl)-2-buten-1-one was obtained by the bromination of 1,3-di(2-thienyl)-2-buten-1-one by NBS in anhydrous
CCl4. The starting butanone was obtained by the condensation of 1-(2-thienyl)-1-ethanone by the action of SOCl2. The reaction of (Z)-4-bromo-1,3-di(2-thienyl)-2-buten-1-one with tertiary amines such as Et3N, pyridine, 1-alkyl-1,3-diazole, 1-alkylbenzimidazole, and 1-alkyl-1,2,4-triazole leads to quaternary salts. The azolium
salts cyclize by the action of base to give di(2-thienyl)azolo[a]pyridinium derivatives. 3-Methyl-6,8-di(2-thienyl)[1,3]thiazolo[3,2-a]pyridin-4-ium
and 2,4-di(2-thienyl)pyrido[2,1-b]benzothiazol-10-ium bromides were obtained by the same procedure but without separating
the intermediate quaternary salts. 相似文献