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1.
We herein report that PtCl4 has proven to be a hydroarylation catalyst with an efficiency and substrate scope superior to previously known methods. This catalyst demonstrated consistent performance with arene-yne substrates of diverse structural features, including propargyl ethers, propargylamines, and alkynoate esters, providing good to excellent yields of the 6-endo products (chromenes, dihydroquinolines, and coumarins). In contrast, Pt(II), Pd(II), and Ga(III) salts were shown to be sensitive to the substitution on the alkyne moiety. PtCl4 is compatible with both terminal and disubstituted alkynes, as well as with various functionalities on the arene ring, including methyl, methoxyl, hydroxyl, protected amine, and halide.  相似文献   
2.
In this article, two kinds of our transition metal-catalyzed olefin arylations are summarized and discussed. The first one is Ir-catalyzed novel anti-Markovnikov hydroarylation of olefins with benzene. Using this reaction catalyzed by [Ir(μ-acac-O,O′,C3)(acac-O,O′)(acac-C3)]2 (acac = acetylacetonato), 1, straight-chain alkylarenes, which were not obtainable by the conventional Friedel-Crafts aromatic alkylation with olefins, were able to be successfully synthesized directly from arenes and olefins with the higher selectivity than that of branched alkylarenes. This is the first efficient catalyst which shows the desirable high regioselectivity. The reaction of benzene with propylene gave n-propylbenzene and cumene in 61% and 39% selectivities, respectively, and the reaction of benzene and styrene afforded 1,2-diphenylethane in 98% selectivity. The reaction of alkylarene and olefin showed meta and para orientations. A wide range of olefins and arenes can be employed for the synthesis of alkylarenes. The mechanism of the reaction involves C–H bond activation of benzene by Ir center to form Ir–phenyl species. The second reaction is Rh-catalyzed oxidative arylation of ethylene with benzene to directly produce styrene, namely one-step synthesis of styrene. The reaction of benzene with ethylene catalyzed by Rh(ppy)2(OAc) (ppyH = 2-phenylpyridine, OAc = acetate), 3 with Cu oxidizing agent gave styrene and vinyl acetate in 77% and 23% selectivities, respectively, in contrast to those by Pd(OAc)2, 47% of styrene and 53% of vinyl acetate. The mechanism of the reaction involves Rh-mediated C–H bond activation of benzene, which appears to be a rate-determining step. Furthermore, Rh complexes in a Rh(I) oxidation state at the beginning of the reaction work as catalysts for the reaction by addition of acacH and O2 without any oxidizing agent, like Cu salt.  相似文献   
3.
Abstract

The regioselective synthesis of Polyhedral oligomeric silsesquioxane (POSS)-based norbornyl imide derivatives through palladium catalyzed Heck coupling reaction was reported on an effective synthetic method to organic–inorganic bio-hybrids serving as advanced materials. The reaction of POSS-based imide derivatives with various aryl iodides catalyzed by palladium acetate in the presence of triethyl amine, as the base, in DMF afforded the products in moderate yields. All new POSS derivatives were structurally characterized by FTIR, 1H, 13C NMR, HRMS and GC/MS analyses.  相似文献   
4.
A catalytic method for the site-selective and enantioselective synthesis of functionalized arenes by the intermolecular hydroarylation of terminal and internal 1,3-dienes with aryl pinacolato boronates is reported. The reactions are promoted by 5.0 mol % of a readily available monodentate phosphoramidite-Ni complex in ethanol, affording a variety of enantioenriched products in up to 96 % yield and 99:1 er. Mechanistic studies indicate that Ni–allyl formation is irreversible and related to the nature of the arylboronate.  相似文献   
5.
Arenes with β‐stereogenic centers are important substructures in pharmaceuticals and natural products. We have developed an asymmetric anti‐Markovnikov hydroarylation of 1,1‐disubstituted olefins by dual palladium and copper hydride catalysis as a convenient and general approach to access these substructures. This efficient one‐step process addresses several limitations of the traditional stepwise approaches. The use of cesium benzoate as a base and a common phosphine ligand for both the Cu‐ and Pd‐catalyzed processes were important discoveries that allow these challenging olefin substrates to be efficiently transformed. A variety of aryl bromide coupling partners, including numerous heterocycles, were coupled with 1,1‐disubstituted alkenes to generate arenes with β‐stereogenic centers.  相似文献   
6.
Abstract

Hydroarylation of styrene and its derivatives with arenes and heteroarenes was studied using Montmorillonite K-10 as an efficient, environmentally benign, economical, greener, and recyclable catalyst. The reaction gives 1,1-diarylalkanes with a very high selectivity and excellent yields in short time with greater substrate compatibility.  相似文献   
7.
Hydroarylation of bicyclic alkenes has been developed using a low‐valent ReI‐catalyzed, directing group‐assisted C?H bond activation strategy. The addition of sodium acetate significantly improves the reaction efficiency; moreover, bicyclic alkenes such as 7‐oxa and aza benzonorbornadienes worked efficiently under this reaction condition. Preliminary mechanistic studies suggest that, after the alkene insertion, the rhenacycle preferentially undergoes protonolysis rather than reductive elimination.  相似文献   
8.
We report a gold-catalyzed intramolecular hydroarylation of unactivated olefins using a combination of AuCl3/AgOTf as the catalytic system affording dihydrobenzopyrans, tetralins and tetrahydroquinolines in good yields. For our preliminary mechanistic studies, we have investigated the kinetic isotope effects with deuterated arene compounds and found that this catalytic hydroarylation is consistent with an electrophilic aromatic substitution process.  相似文献   
9.
Brnsted酸性离子液体作为反应介质和催化剂,实现了苯乙烯类化合物的氢烯基化反应和富电子芳烃参与的氢烷基化反应,取得了优秀的产率和选择性,其产率最高可达到97%,底物适应性比较好,易于放大到克量级,为反式1,3-二芳基1-丁烯化合物和1,1-二芳基乙烷类化合物的制备提供了绿色合成新途径,值得一提的是本方法能以85%的产率高效合成抗蛋白凝聚药物3i,表现出了很好的实用价值.  相似文献   
10.
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