共查询到19条相似文献,搜索用时 78 毫秒
1.
A direct C–H amination reaction of N-Ts-2-Styrylaniline derivatives to realize the synthesis of indole derivatives was developed in the presence of copper salt. A variety of N-Ts-2-Styrylaniline derivatives were transformed into the corresponding indole products in good to excellent yield under mild conditions with the oxidation of potassium persulfate. 相似文献
2.
A facile, direct and environmentally benign conversion of C(sp3)–H bonds to C(sp3)–N bonds using substoichiometric amount of aprotic superelectrophiles polyhalomethane–AlX3 has been achieved by grinding under solvent-free conditions at room temperature in air. It is a general and simple method for the direct amination of adamantanes, and a series of aminoadamantanes of azoles, arylamines or heteroarylamines were obtained in good to excellent yields. The advantages of this amination are atom economy, solvent-free, chemoselectivity, short reaction time and high yields. 相似文献
3.
A C(sp3)–N bond forming reaction between N-alkoxyamides and simple ethers has been developed. In the presence of commercially available 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), a variety of N-methoxyamides and ethers undergo this transformation smoothly to deliver the corresponding products in good yields under visible-light irradiation and metal-free conditions at room temperature. 相似文献
4.
Masahiro Mineno Misayo Sera Tsuyoshi UedaMasahiro Mizuno Mitsuhisa YamanoHideya Mizufune Atsuhiko Zanka 《Tetrahedron》2014
An efficient sequence of Pd catalyzed amination and direct C–H arylation for a synthesis of pharmacologically important α-carbolines is described. The outstanding feature in the synthetic sequence is that a combination of DBU and 2-(dicyclohexylphosphino)biphenyl (DCHPB) plays a critical role to not only enhance the reactivity but also suppress hydrodehalogenation in the direct C–H arylation step. The reaction protocol provides α-carbolines with various substituents including base-sensitive ester and ketone moieties in moderate to excellent yields. Moreover, combination with Cu catalyzed amination further enhanced the versatility of the α-carboline synthesis. 相似文献
5.
A facile and direct synthetic method was developed for the construction of vicinal tricarbonyl compounds (VTCs) in moderate to excellent yields (46–92%), by treating the readily available 1,3-dicarbonyl compounds with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) in the presence of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The reaction pathway involves the DDQ-mediated oxidative activation of sp3 C–H bond and subsequent coupling to TEMPO to form the key intermediate TEMPO-substrate adduct, which can be further converted to VTC products promoted by DDQ. 相似文献
6.
This paper describes a method for nickel catalyzed intramolecular C–H arylation using aryl pivalates as electrophiles. The transformation is efficient for the synthesis of diverse electronically and sterically differentiated dibenzofurans. Additionally, the method could be expanded toward the synthesis of carbazoles. Preliminary mechanistic studies of the transformation are also described. 相似文献
7.
M. A. Nasseri S. A. Alavi B. Zakeri Nasab 《Journal of the Iranian Chemical Society》2013,10(2):213-219
A versatile, alternative and environmentally benign strategy for the synthesis of a series of pyrazoles has been successfully performed in water using PEG–SO3H as an acidic catalyst. The products are obtained in high yield from the one-pot reaction procedure involving dicarbonyl compounds and hydrazines/hydrazides. This new method totally avoids the use of organic acids and toxic or expensive solvents in this reaction. The catalyst is waste-free, easily prepared, and efficiently re-used. 相似文献
8.
Karimi Zarchi Mohammad Ali Darbandizadeh Mohammad Abadi Seyed Shahab Addin 《Research on Chemical Intermediates》2019,45(5):2605-2639
Research on Chemical Intermediates - Facile and efficient protocols for some multicomponent coupling reactions such as the Suzuki reaction and synthesis of polyhydroquinoline and... 相似文献
9.
《Journal of Energy Chemistry》2016,(6)
Rechargeable lithium-oxygen(Li–O_2) batteries have been considered as the most promising candidates for energy storage and conversion devices because of their ultra high energy density. Until now, the critical scientific challenges facing Li–O_2batteries are the absence of advanced electrode architectures and highly efficient electrocatalysts for both oxygen reduction reaction(ORR) and oxygen evolution reaction(OER), which seriously hinder the commercialization of this technology. In the last few years, a number of strategies have been devoted to exploring new catalysts with novel structures to enhance the battery performance. Among various of oxygen electrode catalysts, carbon-based materials have triggered tremendous attention as suitable cathode catalysts for Li–O_2batteries due to the reasonable structures and the balance of catalytic activity, durability and cost. In this review, we summarize the recent advances and basic understandings related to the carbon-based oxygen electrode catalytic materials, including nanostructured carbon materials(one-dimensional(1D) carbon nanotubes and carbon nanofibers, 2D graphene nanosheets, 3D hierarchical architectures and their doped structures), and metal/metal oxide-nanocarbon hybrid materials(nanocarbon supporting metal/metal oxide and nanocarbon encapsulating metal/metal oxide). Finally, several key points and research directions of the future design for highly efficient catalysts for practical Li–O_2batteries are proposed based on the fundamental understandings and achievements of this battery field. 相似文献
10.
Ali Khalafi-Nezhad Farhad Panahi Somayeh Mohammadi Habib Ollah Foroughi 《Journal of the Iranian Chemical Society》2013,10(2):189-200
Silica boron–sulfuric acid nanoparticles (SBSANs) as a solid Lewis-protic acid have been found to be an efficient heterogeneous catalyst in the synthesis of xanthene and acridine derivatives. The SBSAN-catalyzed reaction between carbonyl compound (aldehyde/ketone/ethyl orthoformate) and 5,5-dimethyl-1,3-cyclohexanedione (dimedone) for synthesis of xanthene derivatives is performed under mild conditions with the excellent isolated yield. Also, we can apply a broad scope of carbonyl compounds and amines for efficient synthesis of various acridine derivatives in the presence of SBSAN catalyst. In these multicomponent approaches the SBSAN catalyst can be reused for several times without any treatment in its catalytic activity. 相似文献
11.
Polysubstituted amidines, benzimidazoles and pyrimidines were synthesized via the electrophilic activation of amides with trifluoromethanesulfonic anhydride and 2-chloropyridine. The one-pot protocol is concise and efficient and the substrates are readily available. 相似文献
12.
A new palladium-catalyzed C-H amination of aryl enamines for the synthesis of trifluoromethylated indoles is established. The attractive features of this transformation are the use of atom-economical O2 as the oxidant and easily prepared enamines as substrates. A variety of pharmaceutically important 2-trifluoromethyl indoles can be targeted in moderate to good yields with good functional compatibility. 相似文献
13.
Pyrimidines are synthesized via a direct oxidative one-pot, three-component, reaction between 1,3-diketone, benzaldehydes, and ammonium acetate in the presence of catalytic amounts of Keggin-type heteropolyacids under refluxing conditions in good yields. 相似文献
14.
Vinyl acetate is used as an acetylene equivalent in rhodium(III)-catalysed C-H activation/annulation with aryl ketoxime esters. Extension to an aldoxime ester allows for a concise formal synthesis of decumbenine B. 相似文献
15.
Zhen Gang Liu Nan Li Li Yang Zhong Li Liu Wei Yu 《中国化学快报》2007,18(4):458-460
ZrCl4/Hantzsch 1,4-dihydropyridine is a mild and highly efficient reagent combination for the direct reductive amination.Weakly basic amines such as anilines substituted by electron-withdrawing group and heteroaromatic amines can be reductivelyalkylated with electron rich aldehydes and ketones under mild conditions to form the secondary amines in excellent yields. 相似文献
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18.
An efficient and convenient tert-butyl nitrite-catalyzed selective aerobic oxidation of thiols has been developed. Under the optimal reaction conditions, a number of thiol derivatives including aromatic thiols, heteroaromatic thiols and aliphatic thiols can be converted into their corresponding disulfides in good to excellent yields. 相似文献
19.
A simple and efficient Rh(III)-catalyzed C-H activation and tandem intramolecular cyclization for the synthesis of isocoumarins has been developed. The protocol uses easily available primary benzamides and cyclic 2-diazo-1,3-diketones as starting materials. This reaction proceeds via C-C and C-O bond formation in a single reaction vessel, and the corresponding isocoumarins were obtained in moderate to excellent yields (58%–97%). The well established protocol showed high functional group tolerance, which provided an efficient and alternative route to isocoumarin backbone. 相似文献