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141.
Dmitriy A. Sibgatulin 《Tetrahedron letters》2007,48(15):2775-2779
The reaction of ‘push-pull’ enamines with trifluoromethyl-containing 1,3-dicarbonyl compounds was investigated. It was found that the reaction is sensitive both to the structure of the enamines and to reaction conditions. As a result, a set of various trifluoromethyldialkylanilines was obtained. 相似文献
142.
Morpholinium 5-arylcarbamoyl-3-cyano-6-methyl-4-(5-methyl-2-furyl)-1,4-dihydropyridine-2-thiolates have been obtained by the
interaction of enamines of acetoacetanilides with 5-methyl-2-furfurylidenecyanothioacetamide. Alkylation of the salts gives
thioethers and oxidation gives the corresponding substituted pyridine-2(1H)-thiones. The structure of 2-allylthio-3-cyano-5-(2-methoxyphenylcarbamoyl)-6-methyl-4-(5-methyl-2-furyl)-1,4-dihydropyridine
was studied by X-ray crystallographic analysis.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 51–58, January, 2006. 相似文献
143.
L. M. Potikha N. V. Shkilna V. M. Kisil V. O. Kovtunenko 《Chemistry of Heterocyclic Compounds》2004,40(5):603-615
A study has shown that the acylation of benzo[4,5]imidazol[1,2-b]isoquinolin-11(5H)-one occurs at N(5) or at C(6) depending on the nature of the acylating reagent and the reaction conditions. It was found that principally C-acylation takes place in the absence of base. The reaction with -halo-substituted carboxylic acid chlorides leads to the formation of C-acylated products which are converted to derivatives of the novel heterocyclic system 7H-2a,6b-diazabenzo[b]cyclopenta[l,m]fluorene-1,7(2H)-dione in the presence of base. 相似文献
144.
The reactions of ,-unsaturated trifluoromethyl ketones containing aromatic and heteroaromatic substituents with 1-morpholinocyclopentene, 1-morpholinocyclohexene, and 1-methyl-4-morpholino-1,2,5,6-tetrahydropyridine were studied. The reactions proceeded stereospecifically to give the corresponding bicyclo[3.2.1]octane, bicyclo[3.3.1]nonane, and azabicyclo[3.3.1]nonane derivatives. 相似文献
145.
146.
147.
Julie Aguesseau-Kondrotas Dr. Matthieu Simon Dr. Baptiste Legrand Prof. Jean-Louis Bantigniès Prof. Young Kee Kang Dr. Dan Dumitrescu Dr. Arie Van der Lee Prof. Jean-Marc Campagne Dr. Renata Marcia de Figueiredo Dr. Ludovic T. Maillard 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(30):7396-7401
As three-dimensional folding is prerequisite to biopolymer activity, complex functions may also be achieved through foldamer science. Because of the diversity of sizes, shapes and folding available with synthetic monomers, foldamer frameworks enable a numerous opportunities for designing new generations of catalysts. We herein demonstrate that heterocyclic γ-peptide scaffolds represent a versatile platform for enamine catalysis. One central feature was to determine how the catalytic activity and the transfer of chiral information might be under the control of the conformational behaviours of the oligomer. 相似文献
148.
János T. Csenki Ádám Mészáros Dr. Zsombor Gonda Dr. Zoltán Novák 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(63):15638-15643
The availability and synthesis of fluorinated enamine derivatives such as N-(3,3,3-trifluoropropenyl)heterocycles are challenging, especially through direct functionalization of the heterocyclic scaffold. Herein, a stereoselective N-trifluoropropenylation method based on the use of a bench-stable trifluoropropenyl iodonium salt is described. This reagent enables the straightforward trifluoropropenylation of various N-heterocycles under mild reaction conditions, providing trifluoromethyl enamine type moieties with high stereoselectivity and efficiency. 相似文献
149.
An original one-pot synthesis of bromomethyl ketones is achived using the Petasis reagent (dimethyltitanocene) as a key for enamine generation. Several amides were used to test the limits of the procedure by changing either the alkyl chain R or the amino portion of the starting materials. The enamines generated in situ were allowed to react with bromine at low temperature followed by hydrolysis to yield bromomethyl ketones in excellent yields (85 to 95%). Mechanistic details and optimum conditions for the reaction are briefly discussed. The present approach offers several advantages such as regioselectivity in enamine formation, good yields, mild reaction conditions, and ease of experimentation. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details.] 相似文献
150.
Tino P. Golub Dr. Christian Merten 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(11):2349-2353
Spectroscopic characterizations of key reaction intermediates are often considered the final confirmation of a reaction mechanism. This proof-of-principle study showcases the application of vibrational circular dichroism (VCD) spectroscopy for the characterization of in situ generated reaction intermediates using the key intermediates of enamine catalysis of Jørgensen–Hayashi-type prolinol ether catalysts as model system. By comparison of experimental and computed spectra, the enamines are shown to preferentially adopt an anti-conformation with E-configured C=C bond. For the parent prolinol catalyst, the structure and stereochemistry of the oxazolidine side product is determined as well. This study thus demonstrates that VCD spectra can provide insights into structural preferences of organocatalysts that utilize a covalent activation mechanism. Thereby it outlines new fields of applications for VCD spectroscopy and finally adds the technique to the toolbox of physical organic chemistry for in-depth mechanistic studies. 相似文献