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991.
992.
Dr. Yann Bernhard Brodie Thomson Dr. Vincent Ferey Prof. Dr. Mathieu Sauthier 《Angewandte Chemie (International ed. in English)》2017,56(26):7460-7464
An additive-free nickel-catalyzed α-allylation of aldehydes with allyl alcohol is reported. The reaction is promoted by 1 mol % of in situ formed nickel complex in methanol, and water is the sole by-product of the reaction. The experimental conditions allow the conversion of various α-branched aldehydes and α,β-unsaturated aldehydes as nucleophiles. The same catalyst and reaction conditions enabled a tandem aldol condensation of aldehyde/α-allylation reaction. 相似文献
993.
Hugo Fanlo‐Virgós Dr. Andrea‐Nekane R. Alba Saleh Hamieh Mathieu Colomb‐Delsuc Prof. Dr. Sijbren Otto 《Angewandte Chemie (International ed. in English)》2014,53(42):11346-11350
In biology enzyme concentrations are continuously regulated, yet for synthetic catalytic systems such regulatory mechanisms are underdeveloped. We now report how a substrate of a chemical reaction induces the formation of its own catalyst from a dynamic molecular network. After complete conversion of the substrate, the network disassembles the catalyst. These results open up new opportunities for controlling catalysis in synthetic chemical systems. 相似文献
994.
Stereocontrol of All‐Carbon Quaternary Centers through Enantioselective Desymmetrization of Meso Primary Diols by Organocatalyzed Acyl Transfer 下载免费PDF全文
Christèle Roux Dr. Mathieu Candy Prof. Dr. Jean‐Marc Pons Dr. Olivier Chuzel Dr. Cyril Bressy 《Angewandte Chemie (International ed. in English)》2014,53(3):766-770
The symmetry breaking of meso primary diols bearing a tetrahydropyran ring was employed, using catalytic asymmetric acyl transfer, to control all‐carbon quaternary stereocenters. The planar chiral Fu DMAP catalyst was used in this reaction to reach a high degree of enantioselectivity (up to 97:3 e.r.) through a synergic effect combining a desymmetrization step and a kinetic resolution. Moreover, a beneficial effect was exhibited by C6F6 solvent, yielding the first example of an organocatalyzed asymmetric acyl transfer. The desymmetrized monoesters were then used to obtain, after a straightforward ring opening sequence, complex polyketide building blocks bearing all‐carbon quaternary stereocenters. 相似文献
995.
Dr. Marcello Gennari Bertrand Gerey Dr. Nikita Hall Dr. Jacques Pécaut Dr. Marie‐Noëlle Collomb Mathieu Rouzières Dr. Rodolphe Clérac Dr. Maylis Orio Dr. Carole Duboc 《Angewandte Chemie (International ed. in English)》2014,53(21):5318-5321
Disulfide/thiolate interconversion supported by transition‐metal ions is proposed to be implicated in fundamental biological processes, such as the transport of metal ions or the regulation of the production of reactive oxygen species. We report herein a mononuclear dithiolate CoIII complex, [CoIIILS(Cl)] ( 1 ; LS=sulfur containing ligand), that undergoes a clean, fast, quantitative and reversible CoII disulfide/CoIII thiolate interconversion mediated by a chloride anion. The removal of Cl? from the CoIII complex leads to the formation of a bis(μ‐thiolato) μ‐disulfido dicobalt(II) complex, [Co2II,IILSSL]2+ ( 2 2+). The structures of both complexes have been resolved by single‐crystal X‐ray diffraction; their magnetic, spectroscopic, and redox properties investigated together with DFT calculations. This system is a unique example of metal‐based switchable Mn2‐RSSR/2 M(n+1)‐SR (M=metal ion, n=oxidation state) system that does not contain copper, acts under aerobic conditions, and involves systems with different nuclearities. 相似文献
996.
Cover Picture: Anionic Bipyridyl Ligands for Applications in Metallasupramolecular Chemistry (Chem. Eur. J. 19/2014) 下载免费PDF全文
997.
Borylation of Unactivated Aryl Chlorides under Mild Conditions by Using Diisopropylaminoborane as a Borylating Reagent 下载免费PDF全文
Dr. Hélène D. S. Guerrand Ludovic D. Marciasini Mélissa Jousseaume Dr. Michel Vaultier Dr. Mathieu Pucheault 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(19):5573-5579
The synthesis of arylboronic ester derivatives from aryl chlorides by using aryl(amino)boranes is described. Palladium‐catalyzed coupling between aryl chlorides and diisopropylaminoborane leads to the formation of a C?B bond under mild conditions. A wide range of functional groups are tolerated, making this method particularly useful for the borylation of functionalized aromatics. 相似文献
998.
NIS‐Assisted Aza‐Friedel–Crafts Reaction with α‐Carbamoysulfides as Precursors of N‐Carbamoylimines 下载免费PDF全文
Dr. Nicolas George Mathieu Bekkaye Dr. Aurélien Alix Prof. Dr. Jieping Zhu Dr. Géraldine Masson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(13):3621-3625
A general and practical N‐iodosuccinimide (NIS)‐promoted aza‐Friedel–Crafts reaction of various aromatic nucleophiles with N‐acylimines generated in situ from α‐amidosulfides to give a rapid access to highly functionalized amines is described. The newly developed methodology is very mild, fast, efficient, and complementary. 相似文献
999.
Cationic Bis‐N‐Heterocyclic Carbene (NHC) Ruthenium Complex: Structure and Application as Latent Catalyst in Olefin Metathesis 下载免费PDF全文
Dr. Mathieu Rouen Dr. Pierre Queval Laura Falivene Jessica Allard Loïc Toupet Dr. Christophe Crévisy Frédéric Caijo Dr. Olivier Baslé Prof. Luigi Cavallo Dr. Marc Mauduit 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(42):13716-13721
An unexpected cationic bis‐N‐heterocyclic carbene (NHC) benzylidene ether based ruthenium complex ( 2 a ) was prepared through the double incorporation of an unsymmetrical unsaturated N‐heterocyclic carbene (U2‐NHC) ligand that bore an N‐substituted cyclododecyl side chain. The isolation and full characterization (including X‐ray diffraction studies) of key synthetic intermediates along with theoretical calculations allowed us to understand the mechanism of the overall cationization process. Finally, the newly developed complex 2 a displayed interesting latent behavior during ring‐closing metathesis, which could be “switched on” under acidic conditions. 相似文献
1000.
Mathieu Lafage Dr. Hadrien Heuclin Dr. Xavier‐Frédéric Le Goff Dr. Nathalie Saffon‐Merceron Dr. Nicolas Mézailles 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(51):16995-17003
The synthesis of two novel titanium carbene complexes from the bis(thiophosphinoyl)methanediide geminal dianion 1 (SCS2?) is described. Dianion 1 reacts cleanly with 0.5 equivalents of [TiCl4(thf)2] to afford the bis‐carbene complex [(SCS)2Ti] ( 2 ) in 86 % yield. The mono‐carbene complex [(SCS)TiCl2(thf)] ( 3 ) can also be obtained by using an excess of [TiCl4(thf)2]. The structures of 2 and 3 are confirmed by X‐ray crystallography. A strong nucleophilic reactivity towards various electrophiles (ketones and aldehydes) is observed. The reaction of 3 with N,N′‐dicyclohexylcarbodiimide (DCC) and phenyl isocyanate leads to the formation of two novel diphosphinoketenimines 8 a and 8 b . The bis‐titanium guanidinate complex 9 is trapped as the by‐product of the reaction with DCC. The X‐ray crystal structures of 8 a and 9 are presented. The mechanism of the reaction between complex 3 and DCC is rationalized by DFT studies. 相似文献