全文获取类型
收费全文 | 102篇 |
免费 | 1篇 |
国内免费 | 11篇 |
专业分类
化学 | 114篇 |
出版年
2023年 | 7篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 5篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 8篇 |
2013年 | 4篇 |
2012年 | 3篇 |
2011年 | 9篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 5篇 |
2007年 | 7篇 |
2006年 | 5篇 |
2005年 | 7篇 |
2004年 | 9篇 |
2003年 | 10篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1985年 | 1篇 |
排序方式: 共有114条查询结果,搜索用时 31 毫秒
21.
22.
I. Ara J. R. Berenguer J. Fornis E. Lalinde M. T. Moreno 《Journal of organometallic chemistry》1996,510(1-2):63-70
The dialkynyl complexes cis-[Pt(C CR)2L2] [R = Ph, L2 = 2PPh3, 2PEt3, dppe (dppe = 1,2-bis(diphenylphosphino)ethane]; R ---tBu, L2 = 2PPh3, dppe) react with silver perchlorate in a molar ratio 1:0.5 to give platinum-silver perchlorate salts of the type [Pt2 Ag(C CR)4L4](ClO4) in excellent yield. The X-ray crystal structure of [Pt2Ag(C = CPh)4(PPh3)4](ClO4) 1 shows that the cation is formed by two nearly orthogonal cis-[Pt(C CPh)2(PPh3)2] units connected through a silver cation which is unsymmetrically π-bonded to all four acetylene fragments. Similar reactions of cis-[Pt(C CR)2L2] with one equivalent of AgClO4 afford cationic complexes of general formula [PtAg(C CR)2L2](ClO4), which are believed to be salts, [Pt2Ag2(C CR)4L4](ClO4)2. 相似文献
23.
The sequential reaction of the amino(trimethylsilyl)carbene complex [(CO)5W=C(NH2)C≡CSiMe3] ( 1 ) with nBuLi and [I‐Fe(CO)2Cp] affords the C(carbene)‐N bridged heterobinuclear complex [(CO)5W=C{NHFe(CO)2Cp}C≡CSiMe3] ( 2 ). Desilylation of 1 is achieved by treatment with KF in THF/MeOH. From the reaction of the resulting complex [(CO)5W=C(NH2)C≡CH] ( 3 ) with nBuLi and [I‐Fe(CO)2Cp] two binuclear WFe compounds in a ratio of approximately 1:1 are obtained: the C(carbene)‐C≡C bridged complex 4 and the C(carbene)‐N bridged complex 5 . Repetition of the deprotonation/metallation sequence yields the trinuclear WFe2 complex 6 . One Fe(CO)2Cp fragment in 6 is bonded to the amino group and the other one to the terminal carbon atom of the ethynyl substituent. The analogous reaction of 3 with nBuLi and [Br‐Ni(PMe2Ph)2Mes] gives a ca. 1:1 mixture of two heterobinuclear complexes ( 7 and 8 ). Complex 7 is bridged by the C(carbene)‐C≡C and complex 8 by the C(carbene)‐N fragment. Subsequent reaction of 7 with BuLi and [Br‐Ni(PMe2Ph)2Mes] finally affords the trinuclear WNi2 complex 9 related to 6 . The solid‐state structure of 2 is established by an X‐ray diffraction analysis. The spectroscopic data of the bi‐ and trinuclear complexes indicate electronic communication between the metal centers through the bridging group. 相似文献
24.
Vivian Wing-Wah Yam 《Journal of organometallic chemistry》2004,689(8):1393-1401
This review describes the design and synthesis of a number of luminescent transition metal alkynyls by this laboratory. The luminescence properties of the complexes have been studied and their emission origin elucidated. Some of these complexes have been shown to be ideal building blocks for the design and construction of luminescent molecular rods and materials, in which the luminescence properties can be readily tuned by changing the alkynyl ligands. Some of them also exhibited luminescence switching behaviour with the “ON-OFF” luminescence states modulated by redox processes, metal ion-binding or solvent composition. 相似文献
25.
Ligand exchange of cis-bis(diphenylphosphino)ethylene (dppee) with trans-(Ph3P)2Pt(CCR)2 easily generates the cis-complexes (dppee)Pt(CCR)2 in 64-95% yield. This transformation is used to convert pyridine-containing macrocycle 7 to its cis-analogue 8 and the macrocyclic bipyridine analogue 10 to the unique macrocyclic ligand 11. X-ray structural characterization of trans-complexes 5a and 5b and cis-complexes 6a and 6b are reported, as is the structure of the strained macrocycle 8. 相似文献
26.
Michael I. Bruce Natasha N. Zaitseva Brian W. Skelton Allan H. White 《Journal of Cluster Science》1996,7(2):109-119
The reaction between Ru3(3-2-PhC2C=CPh)(-dppm)(CO)8 and Co2(CO)8 afforded dark red Co2Ru3(4-C2Ph)(3-C2Ph)(-dppm)(-CO)2(CO)9, shown by an X-ray structure determination to contain a strongly twisted Co2Ru3 bow-tie cluster (central Co), to which two PhC2 units derived from cleavage of the original diyne are attached. One a these is strongly interacting with four metal atoms, the other being attached in the familiar 1,22-mode. The dppm ligand remains bridging two of the Ru atoms. 相似文献
27.
Using 4-ethynylphenylferrocene (1) as the building block, a new series of rigid-rod alkynylferrocenyl precursors consisting of fluoren-9-one unit, 2-bromo-7-(4-ferrocenylphenylethynyl)fluoren-9-one (2a), 2,7-bis(4-ferrocenylphenylethynyl)fluoren-9-one (2b), 2-trimethylsilylethynyl-7-(4-ferrocenylphenylethynyl)fluoren-9-one (3) and 2-ethynyl-7-(4-ferrocenylphenylethynyl)fluoren-9-one (4) have been prepared in moderate to good yields. The acetylene complex 4 is a useful precursor for the synthesis of well-defined carbon-rich ferrocenyl heterometallic complexes, trans-[(η5-C5H5)Fe(η5-C5H4)C6H4CCRCCPt(PEt3)2Ph] (5), trans-[(η5-C5H5)Fe(η5-C5H4)C6H4CCRCCPt(PBu3)2CCRC≡CC6H4(η5-C5H4)Fe(η5-C5H5)] (6), trans-[(η5-C5H5)Fe(η5-C5H4)C6H4CCRCCM(dppm)2Cl] (M=Ru (7), Os (8)) (R=fluoren-9-one-2,7-diyl). All new complexes have been characterized by FTIR, NMR and UV-Vis spectroscopies and fast atom bombardment mass spectrometry (FABMS). The molecular structures of 1, 2a, 4, 6 and 8 have been determined by single-crystal X-ray studies where an ironiron through-space distance of nanosized dimension (ca. 42 Å) is observed in the trimetallic molecular rod 6. The electronic absorption, luminescence and electrochemical properties of these carbon-rich molecules were investigated and the data were correlated with the theoretical results obtained by the method of density functional theory. 相似文献
28.
Uwe Rosenthal Perdita Arndt Wolfgang Baumann Vladimir V. Burlakov Anke Spannenberg 《Journal of organometallic chemistry》2003,670(1-2):84-96
Group 4 metallocene mono- and bis-σ-alkynyl complexes of the type L2M(σ-CCR) and L2M(σ-CCR)2 with M=titanium and zirconium in the oxidation states +3 and +4 and L=Cp (η5-cyclopentadienyl) and Cp* (η5-pentamethylcyclopentadienyl) are important compounds for stoichiometric and catalytic C---C single bond coupling and cleavage reactions. Detailed investigations show five-membered metallacyclocumulenes L2M(η4-1,2,3,4-RC4R) as the key intermediates in both reactions of a C---C single bond cleavage of different 1,4-substituted 1,3-butadiynes RCC---CCR to alkynyl groups and the opposite reaction of C---C single bond formation starting from alkynyl groups under the formation of 1,4-substituted 1,3-butadiynes. Depending on different metals M and ligands L, coupling or cleavage is favoured. Combination of both reactions offered the first C---C single bond metathesis in homogeneous solution, which is photocatalyzed and titanocene-mediated. It proceeds via titanocene–mono-alkynyl complexes, which are interesting species also for other stoichiometric and catalytic C---C coupling reactions. Some similarities regarding the σ-to-π conversion exist between the coupling of the alkynyl groups at titano- and zirconocenes to complexed 1,3-butadiynes on one side and the coupling of phenyl groups at chromium to complexed diphenyl on the other side. 相似文献
29.
The reaction of thioiminium salts with zinc acetylides took place at 60 °C to give 3-amino-1-sulfenyl-1,4-enynes in moderate to good yields. Two molecules of acetylides were incorporated into the products. Nucleophilic attack of zinc acetylides to thioiminium salts may initially occur to form alkynyl S,N-acetals, followed by their [1,3]-rearrangement to give 3-sulfenyl-1-aminoallenes. 相似文献
30.
Andrzej Rajca Damian Grobelny Stanisław Witek 《Monatshefte für Chemie / Chemical Monthly》1985,116(11):1363-1365
1,3-Oxathiol-2-ones are converted byn-butyllithium into alkynyl thiolates.
Spaltung von 1,3-Oxathiazol-2-on-Ringen mitn-Butyllithium. Ein neuer Weg zu Alkylthiolaten (Kurze Mitteilung)
Zusammenfassung 1,3-Oxathiol-2-one werden mitn-Butyllithium zu Alkinylthiolaten umgesetzt.相似文献