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201.
M. R. Mazieres C. Roques T. Khim J. P. Majoral R. Wolf M. Sanchez 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):309-312
Abstract In the singlet state phosphenium cations feature both a vacant orbital and a lone pair at the phosphorus center (1). The anticipated amphoterism property of these species can be used for the synthesis of unusual heterocyclic derivatives. Our interest (2) in this type of chemistry bring us to report the reactions of stable phosphenium ions with unsaturated organic reactives i.e imines, a diimines, amidines and isocyanides. 相似文献
202.
Liangzhen Cai Xuanying Qian Wenjing Song Taoping Liu Xiaochun Tao Wanfang Li Xiaomin Xie 《Tetrahedron》2014
A readily accessible catalytic system, PdCl2(Ph3P)2/Ph3P, was developed for the selective arylation of primary anilines with aryl bromides. The strong influence of solvents and bases on the catalytic activity was observed. In refluxing o-xylene, triphenylphosphine shows high efficiency for Pd-catalyzed intermolecular amination reactions. By changing the bases, mono- and diarylation of primary amines could be selectively achieved in high yields. Moreover, the catalytic system showed good toleration for the steric hindrance of anilines. A series of N,N,N′,N′-tetraaryl-1,1′-biphenyl-4,4′-diamines, important intermediates of OLED hole transport materials, were synthesized facilely via coupling reactions between 4,4′-diaminobiphenyls and aryl bromides. 相似文献
203.
考察了编织芳基网络聚合物(KAPs)负载的Rh催化剂(Rh/KAPs)在高碳烯烃氢甲酰化反应中的催化性能. 结果表明,三苯基膦-苯基底KAPs负载Rh催化剂(Rh/KAPs-1)具有优异的高碳烯烃氢甲酰化反应活性,产物醛收率显著高于Rh/SiO2催化剂. 傅里叶变换红外光谱、热重、氮气吸附-脱附、X射线衍射、透射电子显微镜、13C核磁共振和31P核磁共振结果显示,Rh/KAPs-1催化剂具有优异的热稳定性及大的比表面积和多级孔道结构,Rh颗粒处于高度分散状态,并可在反应过程中形成均相催化活性物种. 相似文献
204.
Tarlok S. Lobana Prof. Parminderjit Kaur Geeta Hundal Ray J. Butcher Alfonso Castineiras 《无机化学与普通化学杂志》2008,634(4):747-753
Reactions of pyrimidine‐2‐thione (HpymS) with PdII/PtIV salts in the presence of triphenyl phosphine and bis(diphenylphosphino)alkanes, Ph2P‐(CH2)m‐PPh2 (m = 1, 2) have yielded two types of complexes, viz. a) [M(η2‐N, S‐ pymS)(η1‐S‐ pymS)(PPh3)] (M = Pd, 1 ; Pt, 2 ), and (b) [M(η1‐S‐pymS)2(L‐L)] {L‐L, M = dppm (m = 1) Pd, 3 ; Pt, 4 ; dppe (m = 2), Pd, 5 ; Pt, 6 }. Complexes have been characterized by elemental analysis (C, H, N), NMR spectroscopy (1H, 13C, 31P), and single crystal X‐ray crystallography ( 1 , 2 , 4 , and 5 ). Complexes 1 and 2 have terminal η1‐S and chelating η2‐N, S‐modes of pymS−, while other Pd/Pt complexes have only terminal η1‐S modes. The solution state 31P NMR spectral data reveal dynamic equilibrium for the complexes 3 , 5 and 6 , whereas the complexes 1 , 2 and 4 are static in solution state. 相似文献
205.
Qiong-Hua Jin Li-Na CuiZhong-Feng Li Yu-Han JiangMan-Hua Wu Sen GaoCun-Lin Zhang 《Polyhedron》2012,31(1):472-477
The reactions of palladium(II) chloride, PPh3 and heterocyclic-N/NS ligand in a mixture of CH3CN (5 ml) and CH3OH (5 ml) produced [PdCl2(PPh3)(L1)]·(CH3CN) (1) (L1 = ADMT = 3-amino-5,6-dimethyl-1,2,4-triazine), [PdCl2(PPh3)(L2)] (2) (L2 = 3-CNpy = 3-cyanopyridine), [PdCl(PPh3)(L3)]2·(CH3CN) (3), [PdCl(PPh3)2(HL3)]Cl (4) (HL3 = Hmbt = 2-mercaptobenzothiazole). The coordination geometry around the Pd atoms in these complexes is a distorted square plane. In 3, L3 acts as a bidentate ligand, bridging two metal centers, while in 4, HL3 appears as monodentate ligand with one nitrogen donor atom uncoordinated. Complexes 1-4 are characterized by IR, luminescence, NMR and single crystal X-ray diffraction analysis. All complexes exhibit luminescence in solid state at room temperature. 相似文献
206.
《Journal of Coordination Chemistry》2012,65(10):1111-1118
Lanthanum(III) tris(dithiophosphates), [La{S2P(OR)2}3] (where R=-CH2CH2CH3 or -C6H5) and [La{S2PO2G}3] [where G=-C(CH3)2CH2CH(CH3)-, -CH2C(CH3)2CH2-, -C(CH3)2C(CH3)2- and -CH2CH2CH(CH3)-] were prepared in methanolic solutions of anhydrous LaCl3 and ammonium dithiophosphates. Addition complexes of the type [La{S2P(OR)2}3·nL] and [La{S2PO2G}3·nL] [where n = 1, L = N2C10H8 or N2C12H8 and n = 2, L = P(C6H5)3] were prepared by reaction of lanthanum(III) tris(dithiophosphates) and nitrogen or phosphorus donor bases in benzene. These newly synthesized derivatives have been characterized by elemental analyses, molecular weights, IR, 1H and 31P NMR spectral measurements. Coordination numbers of six and eight are suggested for lanthanum(III) in these derivatives. 相似文献
207.
《Journal of Coordination Chemistry》2012,65(4):676-690
A number of complexes of nickel(II) with 5(2′-hydroxyphenyl)-3-(4-X-phenyl)pyrazolines of the type (C15H12N2O ··· X)2Ni [where X = H, Cl, CH3 and OCH3] were synthesized by the reaction of anhydrous nickel(II) chloride with sodium salts of pyrazoline in 1 : 2 molar ratio. Their addition complexes with 2,2′-bipyridine, 1,10-phenanthroline and triphenylphosphine were prepared in 1 : 1 molar ratio. These complexes were characterized by elemental analyses, molecular weight, magnetic, conductivity, IR, electronic, 1H, 13C, 31P NMR and FAB mass spectral data. All complexes are amorphous. Square planar geometry around nickel confirms the presence of two bidentate pyrazoline ligands in nickel(II)5(2′-hydroxyphenyl)-3-(4-X-phenyl)pyrazolinates. In the addition complexes pyrazoline is monodentate. Bidentate and monodentate pyrazoline was confirmed by IR, 1H, 13C and 31P NMR spectral data. All the metal complexes exhibit very good antibacterial and antifungal activity. Coordination of metal ion has pronounced effect on the microbial activities of the ligand. The brine shrimp bioassay was also carried out to study their in vitro cytotoxic properties; all complexes and adducts display potent cytotoxic activity against Artemia salina. 相似文献
208.
The unusual 1:2 intermediate, generated by the addition of triphenylphosphine (TPP) to dialkyl acetylenedicarboxylates (DAAD) was trapped during the reaction of a Ph3P/RN = C/DMAD binucleophilic system with TFA as an initial proton source in a pseudo-seven-component (7-CR) diastereoselective reaction to give λ5-phosphanylidene bis(2,5-dioxotetrahydro-1H-pyrrole-3-carboxylates) with three stereogenic centers and a phosphorane group in good yields. 相似文献