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191.
Metal‐Free Intramolecular Carbocyanation of Alkenes: Catalytic Stereoselective Construction of Pyrrolo[2,1‐a]isoquinolines with Multiple Substituents 下载免费PDF全文
Jianming Chen Qiuqin Xu Prof. Dr. Weiwei Liao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(43):13876-13880
The first catalytic stereoselective approach to prepare multiple substituted cyclic nitriles by means of a novel metal‐free intramolecular carbocyanation strategy has been developed, which provided an efficient protocol to construct densely functionalized diastereoenriched pyrrolo[2,1‐a]isoquinoline derivates under mild reaction conditions (up to 20/1 d.r., 98 % yield). 相似文献
192.
Zhibin Shu Wenzhi Ji Xi Wang Yujing Zhou Prof. Dr. Yan Zhang Prof. Dr. Jianbo Wang 《Angewandte Chemie (International ed. in English)》2014,53(8):2186-2189
A direct oxidative cyanation of arenes under FeII catalysis with 3,5‐di(trifluoromethyl)phenyl(cyano)iodonium triflate (DFCT) as the cyanating agent has been developed. The reaction is applicable to wide range of aromatic substrates, including polycyclic structures and heteroaromatic compounds. 相似文献
193.
Formation of Four Different Aromatic Scaffolds from Nitriles through Tandem Divergent Catalysis 下载免费PDF全文
Dr. Ju Hyun Kim Prof. Jean Bouffard Prof. Sang‐gi Lee 《Angewandte Chemie (International ed. in English)》2014,53(25):6435-6438
A zinc bromide complex, formed by the sequential reaction of nitriles with a Reformatsky reagent and terminal alkynes, is used as an intermediate for divergent palladium‐catalyzed reactions. The reaction pathway of the intermediate is precisely controlled by the choice of the reaction solvent or the palladium catalyst to quickly form four different aromatic scaffolds—arylamines, aminoindenes, pyrroles, and quinolines—starting from readily available nitriles. 相似文献
194.
Synthesis of α‐Aryl Esters and Nitriles: Deaminative Coupling of α‐Aminoesters and α‐Aminoacetonitriles with Arylboronic Acids 下载免费PDF全文
Guojiao Wu Yifan Deng Chaoqiang Wu Dr. Yan Zhang Prof. Dr. Jianbo Wang 《Angewandte Chemie (International ed. in English)》2014,53(39):10510-10514
Transition‐metal‐free synthesis of α‐aryl esters and nitriles using arylboronic acids with α‐aminoesters and α‐aminoacetonitriles, respectively, as the starting materials has been developed. The reaction represents a rare case of converting C(sp3)? N bonds into C(sp3)? C(sp2) bonds. The reaction conditions are mild, demonstrate good functional‐group tolerance, and can be scaled up. 相似文献
195.
Santosh Takale Smita Manave Kiran Phatangare Vikas Padalkar Nitin Darvatkar 《合成通讯》2013,43(16):2375-2381
An efficient and practical protocol for the preparation of 5-substituted 1H-tetrazole derivatives is reported using phosphomolybdic acid as an effective heterogeneous catalyst. Good yields, simple methodology, and easy workup make this protocol more attractive for the diversity-oriented synthesis of these heterocycle libraries. The catalyst can be recycled three times with good yields. 相似文献
196.
Edith Holtz 《合成通讯》2013,43(17):2959-2966
5‐Cyano‐1,3‐dioxoalkanes were prepared by reaction of 1,3‐dicarbonyl dianions with bromoacetonitrile. 相似文献
197.
Rajiv R. Srivastava Andrew J. Zych David M. Jenkins Hong‐Jun Wang Zhen‐Jia Chen David J. Fairfax 《合成通讯》2013,43(3):431-438
A variety of aryl nitriles were prepared in excellent yield from the palladium(II) acetate–catalyzed cross‐coupling of aryl triflates and zinc cyanide under microwave irradiation conditions. To facilitate purification, polymer‐supported triphenylphosphine was used as the palladium ligand. Comparison to the corresponding thermal conditions revealed much shorter reaction times with comparable yields. 相似文献
198.
Treatment of N-aryl-N-methoxyamides with AlCl3 in EtSH (or Me2S) generates the corresponding N-aryl-N-hydroxyamides in high yields. 相似文献
199.
A. A. Elagamey F. M. A. El-Taweel R. A. N. Abu El-Enein 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2155-2176
Different new 1,3,4-thiadiazolopyridine derivatives (6, 8, 20, 28, and 42) were synthesized from 5-cyanomethyl-1,3-4-thiadiazole (1) and activated nitriles. Also, spiro indolono-thiadiazolopyridine (12) was obtained from the reaction of (1) with 2-(2-oxoindolin-3-ylidene)malononitrile (10). Other heterocyclic derivatives at position-5 in the thiadiazole ring were obtained for possible use as antimicrobial agents. 相似文献
200.
Wolf-Diethard Pfeiffer Horst Dollinger Peter Langer 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):626-637
5-Thioxo-4,6,8,9,10,11-hexahydro-benzo[b]thiopheno[2,3-d]-1,2,4-triazolo[1,5-c]pyrimidines and related compounds were prepared based on cyclizations of 2-isothiocyanato-3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene with aminoketones and carboxylic hydrazides. 相似文献