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31.
A convenient method for the preparation of peraza crown ethers in a one‐pot synthesis in the presence of KF/Al2O3 is presented. 相似文献
32.
Heinrich Hahn Wolfgang Meindl Kurt Utvary 《Monatshefte für Chemie / Chemical Monthly》1985,116(2):157-166
Photochemical chlorination of (CH3NPF3)2 yields ClCH2(NPF3)2CH3(I) and ClCH2(NPF3)2CH2Cl (II). By reaction with organometallics unsymmetric N-substituted hexafluorodiazadiphosphetidines are synthesized. Depending on the nucleophilic strength of the used organometallic the chlorine atom of the N-CH2Cl group can be selectively substituted versus an organic substituent without side-reaction at the phosphorus atom. 相似文献
33.
Reaction of (CH3NPF3)2 with lithiummethylat yields the 2,4-dimethoxysubstituted diazadiphosphetidine which shows a good insecticide effect as proven by screening tests. In order to investigate the influence of the substituent of the nitrogen atom, a number of different 2,4-dimethoxy-substituted diazadiphosphetidines were synthesized. 相似文献
34.
新型2-氨基-5-苯亚甲基-4H-咪唑啉-4-酮衍生物的合成及生物活性 总被引:12,自引:0,他引:12
通过烯基膦亚胺1与芳基异氰酸酯的aza-Wittig反应得到碳二亚胺2,再用2与亲核试剂的成环反应制得10个新型的2-氨基-5-苯亚甲基-4H-咪唑啉-4-酮衍生物4,探讨了碳二亚胺2与不同亲核试剂反应的活性并分离得到了一个胍中问体3i,初步研究了化合物4的生物活性. 相似文献
35.
Gilles Berger Luca Fusaro Michel Luhmer Arie van der Lee Benoit Crousse Franck Meyer 《Tetrahedron letters》2014
We report the synthesis of several new α-trifluoromethylated nitrogen heterocycles, among which azanorbornene and azetidine derivatives, by aza Diels–Alder or iodine-mediated cyclizations. These building blocks were used as starting materials for the formation of fluorinated polymers by ROMP or for ligand design through substitution and click reactions. 相似文献
36.
Michael P. Curtis William H. Bunnelle Thomas G. Pagano Murali Gopalakrishnan 《合成通讯》2013,43(3):321-326
Small heterocyclic amines such as 1,3‐diaza‐bicyclo[3.2.2]nonane are known to be key components of biologically active molecules. A convenient synthesis of this compound utilizing a key Beckmann rearrangement of (Z)‐1‐aza‐bicyclo[2.2.2]octan‐3‐one oxime (6) with conc. H2SO4 under microwave irradiation was achieved. The desired compound (1) was obtained in 20% yield overall. 相似文献
37.
The isothiocyanate 3, obtained from aza‐Wittig reaction of iminophosphorane 2 with CS2, reacts with phenylhydrazine to give thiosemicarbazide 4. Reactions of 4 with alkyl halides in the presence of K2CO3 directly provided 2‐alkylthio‐4H‐imidazol‐4‐ones 6 in good yields. 相似文献
38.
39.
Esmael Rostami Abbas Shockravi Hanif Fattahi Davood Heydarian Shima Shahbanzadeh Minaee Shaghayegh Naghdi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):2066-2077
Dinaphthosulfone aza macrocycles were synthesized from the reaction of diamines and dinaphthosulfone diester (1,1′-sulfoxobis-(2-naphthoxy(2-methyl acetate))) in methanol in the presence of catalytic amounts of para toluenesulfonic acid (p-TsOH). Dinaphthosulfone diester (1,1′-sulfoxobis-(2-naphthoxy(2-methyl acetate))) was synthesized from the corresponding dinaphthosulfide diester and hydrogen peroxide in formic acid at room temperature. Dinaphthosulfide diester was prepared from initial dinaphtholsulfide diol (1,1′-thio bis(2-hydroxy naphthalene)) and methylchloroacetate. 1H NMR spectroscopy showed the unusual splittings for these dinaphthosulfone aza macrocycles, and this finding could be proposed as the role of tetrahedral structure of sulfone functional group, hydrogen bonding in the cavity and size of macrocycle. 相似文献
40.
Esmael Rostami Davood Heidaryan Hanif Fattahi Abbas Shockravi Mehdi Zarei Farokh Rakhshanderu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1924-1934
Four new dinaphthosulfide and dibenzosulfide aza podands were synthesized. The synthesis of these podands was performed under three different reaction conditions: 1) diester, K 2 CO 3 , methanol, and RT; 2) diester, ethanolamine, and microwave (MW); and 3) diacid dichloride, ethanolamine, Et 3 N, CH 2 Cl 2 , RT. Two kinds of diester (dinaphthosulfide and dibenzosulfide) were used for the preparation of dihydroxy podands. These dihydroxy podands were reacted with thionyl chloride to afford dichloro podands. The second route gave excellent yields of dihydroxy podands. Dichloro podands are more soluble than dihydroxy podands in conventional solvents such as methanol, chloroform, and acetonitrile. 相似文献