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51.
Amrita Dey Md Ashif Ali Sourav Jana Sadhanendu Samanta Alakananda Hajra 《Tetrahedron letters》2017,58(4):313-316
The present method describes a palladium-catalyzed cross-dehydrogenative coupling reaction of coumarin and aniline for the synthesis of indole fused coumarin derivatives. The one-pot method is operationally simple and molecular oxygen is used as sole oxidant. The target compounds are obtained in good yields from commercially available precursors. 相似文献
52.
Sankar Hajra 《中国物理 B》2014,(9):129
We point out an error in Eq.(19) in our original paper [Chin. Phys. B 23 040402(2014)] and present the correct equation. 相似文献
53.
Matiur Rahman Avik Kr. Bagdi Dhiman Kundu Adinath Majee Alakananda Hajra 《Journal of heterocyclic chemistry》2012,49(5):1224-1228
4‐(1‐Imidazolium) butane sulfonate is an excellent catalyst for the synthesis of 2,4,5‐trisubstituted and 1,2,4,5‐tetrasubstituted imidazoles through the condensation of 1,2‐dicarbonyl compounds, aldehydes, and ammonium acetate or amine via multicomponent condensation strategy under solvent‐free conditions. The key advantages of this process are high yields, reusability of catalyst, environmental friendliness, easy work‐up and purification of products by nonchromatographic methods. 相似文献
54.
Efficient epoxidation of chiral cinnamic acid derivatives has been achieved by in situ generated dioxiranes of chloroacetones with moderate to good diastereoselectivity (dr up to 90:10) in high yields. Reactivity of cinnamic acid derivatives containing different chiral auxiliaries versus chloroacetones–monochloroacetone 3 (MCA), 1,1-dichloroacetone 4 (DCA) and 1,1,1-trichloroacetone 5 (TCA) and Oxone? loading was studied. Both Oxone? loading and reaction time reduce with an increase of chlorine atoms in the acetone. The use of 1.1 equiv of TCA was found to be effective for the epoxidation of cinnamate substrates and enhances the reaction up to 4–10-fold compared to acetone and that also decreases the Oxone? loading. This method provided methyl (2R,3S)-3-(4-methoxyphenyl)glycidate (?)-2, a key intermediate for the synthesis of diltiazem hydrochloride, with >99% of enantiomeric purity. 相似文献
55.
56.
A concise asymmetric synthesis of the potent dopamine D1 antagonist, ecopipam, has been accomplished in six steps with 33% overall yield via catalytic enantioselective aziridination and subsequent one-pot Friedel–Crafts cyclization of an in situ generated tethered aziridine with high diastereo- and enantioselectivities. 相似文献
57.
New chiral N-chloroimidodicarbonates, which function as efficient chiral chlorinating agents, were designed and synthesized. Among these, C(2)-symmetric (1R,2S,5R)-(-)-menthyl-N-chloroimidodicarbonate 2a provided moderate to good enantioselectivity (up to 40%) for the chlorination of silyl enol ethers to afford alpha-chloroketones only in the presence of a suitable Lewis acid such as Sm(OTf)(3). 相似文献
58.
Basit H Van der Heyden A Gondran C Nysten B Dumy P Labbé P 《Langmuir : the ACS journal of surfaces and colloids》2011,27(23):14317-14328
Tethered bilayer lipid membranes (tBLMs) are designed on mixed self-assembled monolayers (SAMs) of a novel synthetic anchoring thiol, 2,3-di-o-palmitoylglycerol-1-tetraethylene glycol mercaptopropanoic acid ester (TEG-DP), and a new short dilution thiol molecule, tetraethylene glycol mercaptopropanoic acid ester (TEG). tBLM formation was accomplished by self-directed fusion of small unilamellar vesicles of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine. The influence of the dilution of the anchoring thiol molecule in the SAM on the vesicle fusion process and on the properties of the resulting tBLMs is studied. It is observed by quartz crystal microbalance that vesicle fusion is a one-step process for a pure TEG-DP SAM as well as for mixed SAMs containing a high concentration of the anchoring thiol. However, upon dilution of the anchoring thiol to moderate concentrations, this process is decelerated and possibly follows a pathway different from that observed on a pure TEG-DP SAM. Electrochemical impedance spectroscopy is used to qualitatively correlate the composition of the SAM to the electrical properties of the tBLM. In this paper we also delineate the necessity of a critical concentration of this anchoring TEG-DP thiol as a requisite for inducing the fusion of vesicles to form a tBLM. 相似文献
59.
An efficient process has been developed for the synthesis of 2,2,4‐trisubstituted‐1,2‐dihydroquinolines in good yields through a simple one‐pot condensation between anilines and ketones in the presence of zinc triflate as a catalyst at room temperature under solvent‐free conditions. 相似文献
60.
Mrittika Mohar Sumit Ghosh Alakananda Hajra 《Chemical record (New York, N.Y.)》2023,23(11):e202300121
Harnessing visible-light in organic synthesis is one of the most effective methods that aligns with green and sustainable chemistry principles and hence skyrocketed in the last two decades. Similarly, three-component 1,2-dicarbofunctionalization of alkenes and alkynes has recently been a great choice to construct complex molecular systems in an easy and rapid manner. Therefore, light-induced reactions can be an excellent alternative to carry out 1,2-dicarbofunctionalization reactions, and very recently, organic chemists across the globe have fascinated us with their interesting articles. In this present review, we have summarized the recent advancements in the area of visible light induced three-component 1,2-dicarbofunctionalization of alkenes and alkynes till March 2023. We have categorized the discussion based on the catalysts used to carry out the transformations for better understanding and different important aspects of these transformations have also been covered. 相似文献