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Karsten Schubert Theodor Alpermann Tobias Niksch Helmar Grls Wolfgang Weigand 《无机化学与普通化学杂志》2006,632(6):1033-1042
Synthesis and Analytical Characterization of Functionalized β‐Hydroxydithiocinnamic Acids and their Esters. Complex Chemistry towards Nickel(II), Palladium(II), and Platin(II) Starting from silyl‐protected 4‐hydroxy acetophenone ( 1 ) the 1,1‐ethenedihiolato complexes 3 – 5 were synthesised using carbon disulfide and potassium‐tert‐butylate as a base. After being deprotected, the resulting 4‐hydroxy‐substituted complexes 6 – 8 were esterified with DL‐α‐lipoic acid to obtain the compounds 9 – 11 . The resulting complexes were characterized using NMR spectroscopy, mass spectrometry and IR spectroscopy. 3‐substituted β‐hydroxydithiocinnamic acid methyl ester ( 12 ) was obtained via an analogous path of reaction using silyl‐protected 3‐hydroxy acetophenone ( 2 ), carbon disulfide and methyl iodide. After removing of the silyl group the resulting hydroxy group was esterified with DL‐α‐lipoic acid. Using the dithioacid ester 14 as a ligand the NiII ( 15 ), PdII ( 16 ) and PtII ( 17 ) [O,S] complexes were obtained. 相似文献
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Bose G Nguyen VT Ullah E Lahiri S Görls H Langer P 《The Journal of organic chemistry》2004,69(26):9128-9134
The Lewis acid mediated domino "[3+3]-cyclization-homo-Michael" reaction of 1,3-bissilyl enol ethers with 1,1-diacylcyclopropanes allows an efficient one-pot synthesis of functionalized salicylates containing a halogenated side chain. A great variety of substitution patterns could be realized by variation of the starting materials and of the Lewis acid. The mechanism of the domino process was studied. 相似文献
4.
Chiral salicylidenphenethylamines (R)‐HA or (S)‐HA , 2‐salicylidenfurfuryl‐imines HB , and 2‐salicylidenaminoethanol HC react with sodium hydride or sodium hexamethyldisilylamide to form the sodium complexes [Na(R)‐A] 4 · 0,5 Et 2 , [Na(S)‐A] 4 · 0,5 Et 2 O (1) , [NaB] 4 · 0,5 Ph‐Me (2) and [(dme)NaC] 4 (3) . In the presence of 18‐crown‐6 the complex [Na(18‐crown‐6)(thf) 2 ] 2 [Na 2 (C)] 4 · THF (4) can also be isolated. The crystal structure analyses of both 1 and 2 show that heterocubane structures with a Na4O4 frame work are formed. Additionally, the imine nitrogen atom is bonded at the Na atom which has the coordination number 4 in 1 . Additional coordination of the furfuryl oxygen atom results in the coordination number five for the sodium atom in 2 . In 3 which is also a tetramer, two Na2O2 units are connected via two imino‐ethanol bridges Na(1)‐N(=CH‐phenolat)‐CH2CH2‐OH‐Na(2A). The crystal structure analysis displays that 4 is an ionic compound consisting of two [(thf)2Na(18‐crown‐6)]+ cations and the dinuclear dianion [Na 2 (C) 4 ] 2? . Both 1 and 2 are carboxylation reagents which transfer CO2 to 2‐fluoropropiophenone. 1 is more active than 2 , but 3 and 4 are inactive. 相似文献
5.
A new computer controlled equipment for carrier concentration profile determination of silicon structures by a spreading resistance technique is presented. The required data and plots can easily be obtained by means of a new software package, which has been specially developed for this purpose. Measurements have been performed on different structures in order to verify the suitability of both the measuring system and the software package. The reproducibility has been found to be within 5% for the investigated structures. 相似文献
6.
Binuclear Nickel(0) Alkyne Coordination Compounds – Correlation between Ligand Periphery and Supramolecular Structure Reaction of Ni(cdt: 1,5,9-cyclododecatriene) with functionalized alkynes and subsequent reaction with ethylenediamines gives binuclear compounds of the type (diamine)Ni(μ-alkyne)Ni(alkyne). Compounds with alkyne-diols (N?N)Ni2(HOR1R2C? C?C? CR1R2OH)2 show supramolecular structures in which two identical intramolecular and one intermolecular hydrogen bonds are realized. 1 and 2 (chelate ligand in each case N,N,N′,N′-tetramethylethylenediamine, TMEDA, in 1 R1 = R2 = Me, in 2 R1 = R2 = Et) polymer-like chains are built up by connecting the binuclear units. Via two intermolecular hydrogen bonds per organometallic unit in 1 and via one intermoleculare hydrogen bond in 2 the chains are connected to give double chains. By substitution of one methyl group of TMEDA by hydrogen ( 3 : R1 = R2 = Me) a polymerlike network is produced by connecting the polymer-like chains. In compound 4 in which one of the methyl groups of TMEDA is substituted by CH2CH2NMe2 the polymer-like chains remain unconnected. In 5 (diamine = TMEDA, alkyne = (CH3)3C? C?C? CMe2OH) one intermolecular hydrogen bond per organometallic unit is observed forming again polymer-like chains that are independent of each other. 相似文献
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Simon Sengupta Philipp Schüler Dr. Helmar Görls Dr. Phil Liebing Dr. Sven Krieck Prof. Matthias Westerhausen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(50):e202201359
The in situ Grignard Metalation Method (iGMM) is a straightforward one-pot procedure to quickly produce multigram amounts of Hauser bases R2N-MgBr which are valuable and vastly used metalation reagents and novel electrolytes for magnesium batteries. During addition of bromoethane to a suspension of Mg metal and secondary amine at room temperature in an ethereal solvent, a smooth reaction yields R2N-MgBr under evolution of ethane within a few hours. A Schlenk equilibrium is operative, interconverting the Hauser bases into their solvated homoleptic congeners Mg(NR2)2 and MgBr2 depending on the solvent. Scope and preconditions are studied, and side reactions limiting the yield have been investigated. DOSY NMR experiments and X-ray crystal structures of characteristic examples clarify aggregation in solution and the solid state. 相似文献
10.
Veselin Nasufović Dr. Florian Küllmer Johanna Bößneck Dr. Hans-Martin Dahse Dr. Helmar Görls Dr. Peter Bellstedt Dr. Pierre Stallforth Prof. Dr. Hans-Dieter Arndt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(45):11633-11642
The first total synthesis of the actin-stabilizing marine natural product geodiamolide H was achieved. Solid-phase based peptide assembly paired with scalable stereoselective syntheses of polyketide building blocks and an optimized esterification set the stage for investigating the key ring-closing metathesis. Geodiamolide H and synthetic analogues were characterized for their toxicity and for antiproliferative effects in cellulo, by characterising actin polymerization induction in vitro, and by docking on the F-actin target and property computation in silico, for a better understanding of structure-activity relationships (SAR). A non-natural analogue of geodiamolide H was discovered to be most potent in the series, suggesting significant potential for tool compound design. 相似文献