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11.
IntroductionTheadvantageofmacrocyclicoligomersasprecursorsforthepreparationofhighperformancepolymersviaring openingpolymerization (ROP)hassparkedmuchinterestintheareaofadvancedthermoplasticcomposites.1 3Andaseriesofcyclicoligomerssuchascarbonates,4 arylesters ,5,6 ethers,7amides8andsulfides9,10 hasbeensuccessfullysynthesized .Recently ,Nishikuboetal.11reportedakindofnovelmacro cyclicoligomerscontainingthioestergroupspreparedbycon densationofbis(4 mercaptophenyl)sulfidewitharomaticaciddichlo… 相似文献
12.
Cage organometallosiloxanes were synthesized according to a new procedure using monomeric organoalkoxysilanes as the starting
compounds. The latter were subjected to hydrolysis immediately before the exchange reaction of sodium silanolate with metal
halides. Difficultly accessible metallovinylsiloxanes, metallomethylsiloxanes, and metallosiloxanes containing a functional
group in the organic radical at the silicon atom can be readily prepared according to the method proposed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2530–2532, December, 1998. 相似文献
13.
N. Suryakiran 《Tetrahedron letters》2006,47(23):3853-3856
An efficient and convenient synthesis of β-ketosulfones is described. Reaction of an α-haloketone with sodium alkyl/aryl sulphinate yields the corresponding β-ketosulfone promoted by polyethylene glycol (PEG-400) as an efficient reaction medium. 相似文献
14.
15.
Pd(PPh3)4 catalyzed Suzuki-Miyaura cross-coupling reactions of 4-tosyloxycoumarins or 4-tosyloxyquinolin-2(1H)-one with various potassium aryl trifluoroborates afforded the corresponding 4-substituted coumarins or 4-substituted quinolin-2(1H)-ones in good to excellent yield. 相似文献
16.
Gololobov Yu. G. Petrovskii P. V. Ivanova E. M. Linchenko O. A. Schmutzler R. Ernst L. Jones P. G. Karaçar A. Freytag M. Okucu S. 《Russian Chemical Bulletin》2003,52(2):427-436
The reactions of meta—para-substituted aryl isocyanates with phosphorus-containing 1,3-zwitterions, which proceed with the CN migration of the CO2Et group to form the corresponding carbamates, were extended to ortho-substituted aryl isocyanates. The influence of the steric and electronic effects of the ortho substituents in the aromatic rings of aryl isocyanates on the ease of this rearrangement is qualitatively considered. 相似文献
17.
D. L. Lipilin A. Yu. Tyurin O. Yu. Smirnov A. M. Churakov Yu. A. Strelenko V. A. Tartakovsky 《Russian Chemical Bulletin》2006,55(7):1239-1242
Treatment of 2-(tert-butyl)-1,2,3,4-benzotetrazinium tetrafluoroborates with sodium thiocyanate afforded 2-(tert-butylazo)phenyl isothiocyanates 3, which exist in equilibrium with 2-(tert-butyl)-1,2,4-benzotriazine-3(2H)-thiones 3′. The equilibrium depends on the substituents R in the benzene ring: the percentage of the open isomer 3 is about 20% for R = H or Me; for R = Cl or Br, the equilibrium is completely shifted to cyclic isomer 3′. The equilibrium is slow on the time scale of the 1H and 13C NMR experiments. For compounds 3a/3′a (R = H), the spectra at 24 °C show two sets of signals, while those at 0 °C contain only signals for isomer 3′a.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1192–1195, July, 2006. 相似文献
18.
Suzuki-Miyaura coupling was achieved on a variety of aryl chlorides by using di(2,6-dimethylmorpholino)phenylphosphine (L1) as a bulky electron-rich monoaryl phosphine ligand. We report the couplings of various chlorobenzenes and heteroaryl chlorides. 相似文献
19.
The general synthesis and a novel intramolecular nucleophilic aromatic substitution (SNAr) reaction of 2-carboxamido-3-arylquinazolin-4-ones, a potentially useful scaffold in the field of medicinal chemistry, are described. The synthetic utility of the SNAr reaction as a tool for the synthesis of secondary aryl amines, including diaryl amines, is also demonstrated. 相似文献
20.