共查询到20条相似文献,搜索用时 15 毫秒
1.
Quinoxaline derivatives have been synthesized in a very short time with excellent yields by the condensation of 1,2-diamines with aliphatic or aromatic 1,2-dicarbonyl compounds or benzilmonoxime in the presence of silica sulfuric acid as a very inexpensive solid acid catalyst at room temperature. The recovery and reuse of the catalyst are also satisfactory. 相似文献
2.
Shekhar KC Roshan K. Dhungana Namrata Khanal Prof. Ramesh Giri 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(21):8124-8128
We report a Ni-catalyzed regioselective α-carbonylalkylarylation of vinylarenes with α-halocarbonyl compounds and arylzinc reagents. The reaction works with primary, secondary, and tertiary α-halocarbonyl molecules, and electronically varied arylzinc reagents. The reaction generates γ,γ-diarylcarbonyl derivatives with α-secondary, tertiary, and quaternary carbon centers. The products can be readily converted to aryltetralones, including a precursor to Zoloft, an antidepressant drug. 相似文献
3.
ShunJunJI ShunYiWANG ZhiLiangSHEN MingFengZHOU 《中国化学快报》2003,14(12):1246-1248
The rate of formation of aldol condensation products by being ground acetylferrocene and various aromatic aldehydes without solvent was dramatically enhanced comparing to ,the conventional methods. The yield is high (84 % - 96 %) at room temperature. 相似文献
4.
An efficient catalytic decarboxylative acylation of unactivated sp(2) (alkenyl) C-H bonds has been developed. Various substituted α-oxocarboxylic acids with different electronic properties react under mild conditions to afford a diverse range of β-acyl enamide products in good yields. The reaction is proposed to proceed via a cyclic vinylpalladium intermediate, facilitating the decarboxylative dehydrogenative process with enamide coupling partners. 相似文献
5.
A mild and efficient synthesis of 1-aryl-1-fluoroethenes from benzothiazolyl (aryl)fluoromethyl sulfones and paraformaldehyde, under DBU- or Cs(2)CO(3)-mediated conditions at room temperature, is described. A comparable diethyl fluoro(naphthalen-2-yl)methylphosphonate reagent does not react with paraformaldehyde under these mild conditions. The utility of the methodology for synthesis of terminal α-fluoroalkenes bearing electron-withdrawing functionalities is also shown. 相似文献
6.
Chaoqiang Wu Zhicheng Bao Bowen Dou Prof. Dr. Jianbo Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(7):2294-2298
A transition-metal-free method for the alkylation of gem-diborylalkanes with α,β-unsaturated ketones has been developed. It is demonstrated that the α-boryl radicals can be generated efficiently from gem-diborylalkanes with the aid of catechol and oxidants. The α-boryl radicals formed through such process can be engaged in conjugate addition reaction with α,β-unsaturated ketones. This transformation is a straightforward method for the synthesis of γ-borylketones. 相似文献
7.
V. V. Klyubin K. A. Klyubina K. N. Makovetskaya 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(2):295-299
The kinetics of crystalline iodine dissolution in ethanol at room temperature and 60°C is studied using the electronic absorption spectra of iodine solutions. Dissolution is shown to proceed for more than three months. It is found that the process begins with the formation of hydroiodic acid HI and is complete with the formation of I 3 ? anions. 相似文献
8.
Metal and semiconductor nanoparticles with nonspherical shapes, such as wires1, cubes2,3 and belts4, have been drawing a great interest in scientific community as a result of their physical and chemical properties being distinctly different from conventio… 相似文献
9.
10.
Synthesis of Crystalline Nanosized Titanium Dioxide via a Reverse Micelle Method at Room Temperature
Crystalline TiO2 nanoparticles were synthesized by hydrolysis of titanium tetrabutoxide in the presence of hydrochloric acid in Np-5(lgepal CO-520)/ cyclohexane reverse micelle solution at room temperature.Pure rutile nanoparticles were obtained at an appropriate acid concentration.The influences of various reaction conditions such as the concentration of acids,water content value (2=[H2O]/[Np-5]) on the formation,erystal phase,morphology,and size of the TiO2 particles were investigated. 相似文献
11.
Abbas Shockravi Mahdieh Sadeghpour Masoomeh Zakeri Ebrahim Abouzari-Lotf Abolfazl Olyaei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):808-815
Some new oxygen–sulfur, multibenzo macrocyclic ligands containing amide groups have been prepared using the macrocyclization process with the reaction of 2,2′-thiobis-[4-methyl(2-aminophenoxy)phenyl ether] as a symmetrical diamine with appropriate dicarboxylicacid dichlorides in moderate yields. This macrocyclization led to the formation of di- and tetramide macrocycles. These reactions were routinely carried out at ambient temperature in CH2Cl2 as solvent in high dilution without template effect conditions. It is found that sulfur the atom affects the rigidity of the macrocycles and diastereotopicity of nuclei in the ring of these series of macrocyclic compounds. 相似文献
12.
13.
Rapid Synthesis of Lead Oxide Nanorods by One-step Solid-state Chemical Reaction at Room Temperature
A simple and facile method was reported to synthesize lead oxide nanorods. Nanorods of lead oxide were obtained directly from grinding solid metal salt and sodium hydroxide in agate mortar with the assistance of a suitable nonionic surfactant in only one step, which is different from the result of hydroxide in solution. The product has been characterized by XRD, TEM and SEM. The formation mechanism of rod-like morphology is discussed and the surfactant plays an important soft-template role in modifying the interface of solid-state reaction and according process of rod-formation. 相似文献
14.
A novel and environmentally benign synthetic method for ureas through hydrogen peroxide–promoted desulfurization of thioureas at room tepemperature via grinding is reported. As compared with the traditional method, this one is manipulatively simple and the oxidant is low cost, highly active, and environmentally friendly. 相似文献
15.
A simple, efficient, and general method has been developed for the one-pot, three-component synthesis of α-aminophosphonates from a condensation reaction of trimethyl phosphite, aldehydes, and amines in the presence of sodium dihydrogen phosphate under solvent-free conditions. Thus, α-aminophosphonates were synthesized relatively quickly in good yields at room temperature. 相似文献
16.
β-Chloro-β-nitroolefin derivatives 2 were prepared from the reaction of β-nitroolefins 1 with HCl / DMF / Oxone system in moderate to good yields. 相似文献
17.
Julia Struwe Dr. Korkit Korvorapun Agnese Zangarelli Prof. Dr. Lutz Ackermann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16237-16241
The ruthenium-catalyzed synthesis of diarylmethane compounds was realized under exceedingly mild photoredox conditions without the use of exogenous photocatalysts. The versatility and robustness of the ruthenium-catalyzed C−H benzylation was reflected by an ample scope, including multifold C−H functionalizations, as well as transformable pyrazoles, imidates and sensitive nucleosides. Mechanistic studies were indicative of a photoactive cyclometalated ruthenium complex, which also enabled versatile C−H allylations. 相似文献
18.
Baylis-Hillman alcohols are excellent sources of the allylic halides ArCHCH(CH2X)(CO2R) (X=Br, Cl; R1=Me, Et, But). The Z double bond isomers are attained in high isomeric purity (>14:1, Z/E). The halides are chemo- and regiospecifically transformed into the acrylates (ArCHR2)C(CH2)(CO2R1) on treatment with Zn(R2)2 (R2=Me, Et, CH2TMS, CH2SiMe2OMe) or PrZnBr in the presence of catalytic amounts of copper(I) salts (0.5-20 mol%) in high yield. 相似文献
19.
Sven C. Richter Prof. Dr. Martin Oestreich 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(36):8508-8512
A sequence of a Baeyer–Villiger oxidation and a Lewis acid-promoted reduction of the resulting formate with Et3SiH enabled the metal-free formal decarbonylation of tertiary and secondary aliphatic aldehydes. The new methodology mimics the biosynthetic decarbonylation pathway through oxidative C−C bond cleavage rather than the C(O)−H bond activation known from conventional Tsuji–Wilkinson-type reactions. The substrate scope is complementary to existing transition-metal-catalyzed protocols. 相似文献
20.
Yun Xia QI Shi Gui ZHAO Wei Feng JIANG Xin Xin YANG 《中国化学快报》2006,17(4):533-536
Allyl terminated polyether was used to improve the hydrophilicity of addition-cured room temperature vulcanization silicone rubber. With the increasing of the polyether, both the hydrophilicity and water absorbed of the vulcanizates were increased. The mechanical properties were also improved by adding the polyether. The result showed that 1.5wt% of the polyether provided the silicone rubber with proper hydrophilicity. 相似文献