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111.
112.
The electronpoor double-bond of cyclic vinylphosphine oxides (1, 3 and 4) is easily reduced by borane in a selective manner to give the corresponding saturated derivatives (2, 4 and 5, respectively) Under forcing conditions, change of the functionality may also take place. 相似文献
113.
Nickel‐Catalyzed Cross‐Electrophile Coupling with Organic Reductants in Non‐Amide Solvents 下载免费PDF全文
Dr. Lukiana L. Anka‐Lufford Kierra M. M. Huihui Dr. Nicholas J. Gower Dr. Laura K. G. Ackerman Prof. Dr. Daniel J. Weix 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(33):11564-11567
Cross‐electrophile coupling of aryl halides with alkyl halides has thus far been primarily conducted with stoichiometric metallic reductants in amide solvents. This report demonstrates that the use of tetrakis(dimethylamino)ethylene (TDAE) as an organic reductant enables the use of non‐amide solvents, such as acetonitrile or propylene oxide, for the coupling of benzyl chlorides and alkyl iodides with aryl halides. Furthermore, these conditions work for several electron‐poor heterocycles that are easily reduced by manganese. Finally, we demonstrate that TDAE addition can be used as a control element to ‘hold’ a reaction without diminishing yield or catalyst activity. 相似文献
114.
Triphenylphosphine‐Mediated Deoxygenative Reduction of CF3SO2Na and Its Application for Trifluoromethylthiolation of Aryl Iodides 下载免费PDF全文
Prof. Yi Yang Long Xu Siqi Yu Dr. Xiaoqiang Liu Yu Zhang Prof. David A. Vicic 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):858-863
We report herein a practical method for taming Langlois’ reagent CF3SO2Na to generate CuSCF3 by a triphenylphospine‐mediated deoxygenative reduction process. This chemistry highlights a novel utilization of the inherent CF3S skeleton of Langlois’ reagent as a CF3S feedstock under mild conditions. The CuSCF3 intermediate generated by this protocol can react with a wide array of supporting ligands to furnish several air‐stable [LCu(SCF3)] complexes as valuable trifluoromethylthiolating agents. In addition, the CuSCF3 intermediate can be directly employed for the trifluoromethylthiolation of (hetero)aryl iodides with operational simplicity and atomic efficiency. 相似文献
115.
Masaki Takahashi Ayato YamamotoToshiyasu Inuzuka Tetsuya SengokuHidemi Yoda 《Tetrahedron》2011,67(49):9484-9490
Lipophilic bisanthracene-based fluorophore and its derivatives were synthesized by the Suzuki-Miyaura cross-coupling reaction of 9-anthrylboronic acid with a substituted dibromobenzene. In addition to desirable fluorescent properties, these molecular systems were demonstrated to serve as versatile building blocks toward the synthesis of two types of new light-harvesting dendrimers due to their chemical stability. 相似文献
116.
Ian J.S. Fairlamb Anant R. Kapdi Jason M. Lynam Richard J.K. Taylor Adrian C. Whitwood 《Tetrahedron》2004,60(27):5711-5718
A new palladium(II) precatalyst for Suzuki cross-coupling of aryl halides and organoboronic acids has been identified, namely bis(triphenylphosphine)palladium(II)succinimide [(Ph3P)2Pd(N-Succ)2] 2. The precatalyst is easily prepared from palladium(0) precursors, such as (Ph3P)4Pd or Pd2dba3·CHCl3/Ph3P and succinimide, is air, light and moisture stable, and may be employed with a variety of substrates to give the cross-coupled products, in good yields and in reasonable time, at relatively low catalyst loadings. 相似文献
117.
Ishmuratov G. Yu. Yakovleva M. P. Galyautdinova A. V. Muslukhov R. R. Tolstikov G. A. 《Russian Chemical Bulletin》2003,52(3):740-744
A new procedure was developed for the synthesis of racemic analogs of 1,5-dimethyl-branched insect pheromones based on monoalkylation of ethyl acetoacetate with 1-acetoxy-5-bromo-3-methylpentane produced upon decyclization of 4-methyltetrahydropyran. 相似文献
118.
Abstract1-Tributylstannyl glycals were applied as versatile tools in the Pd(0)-mediated synthesis of glycal phthalonitrile conjugates. Likewise, selective homo-coupling of 1-tributylstannyl glycals furnishing C1-C1’ linked glycal dimers was investigated by using Pd(II)-species. For both Stille type couplings the rate-accelerating effect of copper(I) thiophene-2-carboxylate (CuTC) was exploited. The synthesis of stannylated glycal precursors was significantly improved by establishing a one-pot two-step procedure via glycosyl sulfoxides. 相似文献
119.
Keith D. Barnes Ping Chen Yingyan Chang Robert M. Lewis Christopher M. Manley Nicholas J. Mayhew 《合成通讯》2013,43(1):67-72
A convergent synthesis of indoprofen via a Buchwald coupling approach is reported. Using this methodology, indoprofen and a set of analogs of indoprofen were readily prepared. 相似文献
120.
Constantin Mamat Markus FrankeTim Peppel Martin KöckerlingJörg Steinbach 《Tetrahedron》2011,67(25):4521-4529
An elegant and efficient synthesis approach for the preparation of novel benzoate and nicotinate containing phosphanes is presented. This reaction path has a broad substrate scope. Thus, various functionalized phosphanes were obtained in high yields using an esterification procedure under Steglich conditions. A facile blocking of the phosphorus atom with BH3 was carried out. BH3 as easily insertable and removable protecting group enables a further derivatization of the benzoate residue. The prepared phosphane derivatives proved to be valuable labeling building blocks for the implementation of a bioorthogonal (radio-)fluorination strategy and were applied for labeling purposes using the traceless Staudinger ligation. For this purpose, a selection of azide-functionalized small organic and bioactive sample molecules was prepared. Furthermore, a mild and selective (radio-)fluorination of these derivatives is demonstrated adopting this bioorthogonal ligation method. 相似文献