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41.
Ken-ichi Yamada 《Tetrahedron letters》2004,45(35):6595-6597
Cycloalkyl radicals were directly generated from cycloalkanes via C-H bond cleavage by the action of dimethylzinc-air and underwent an addition reaction with N-tosylimines, giving aminoalkylation products in fair to high yields. 相似文献
42.
Aránzazu Sánchez 《Tetrahedron》2004,60(51):11843-11850
Tris(trimethylsilyl)silane (TTMSS) and azobisisobutironitrile (AIBN) promote the intramolecular heteroarylation of arenesulfonamides with pyridyl radicals under thermal conditions. The arenesulfonamides are easily prepared from pyridinium N-2′-pyridylaminide. The heteroarylation process involves pyridyl radical cyclization and ipso substitution. 相似文献
43.
Yannick Borguet 《Tetrahedron letters》2007,48(36):6334-6338
The first monomode microwave-assisted atom transfer radical additions (ATRA) of carbon tetrachloride to various olefins were successfully performed, affording the adducts with almost quantitative yields in less than 10 min at 160 °C. 相似文献
44.
For a number of free radicals the results of non-empirical (ab initio) and semi-empirical (INDO, DEPAC, CNDO/SP) calculations of the isotropic hyperfine coupling constants are compared. 相似文献
45.
Ciguatoxin C-CTX-1 was isolated as a principal causative toxin of ciguatera seafood poisoning in the Caribbean Sea, and is structurally classified as a ladder-shaped polycyclic ether. In this Letter, we report the convergent synthesis of the pentacyclic left half of C-CTX-1, based on a newly developed acyl radical strategy. 相似文献
46.
47.
Richard Bersohn 《中国化学会会志》2002,49(3):291-300
There is much new information available on radicals containing C, H and O atoms. Indeed, most of the data discussed in this review did not exist twenty years ago. New, more powerful laser and microwave experimental techniques have greatly expanded our knowledge of the energetics, spectra, reactions and decomposition processes of these radicals. This review attempts to give a unified discussion of the radicals. 相似文献
48.
[RuCl2(p-cymene)] complexes containing triarylphosphine ligands with various substituents at the para position were used to catalyse the atom transfer radical addition of carbon tetrachloride to various olefins, and their catalytic activities were nicely correlated with their electrochemical parameters. 相似文献
49.
Yuri I. Gorlov Ivan I. Ukrainsky Vladimir V. Penkovsky 《Theoretical chemistry accounts》1974,34(1):31-38
The UHF-CNDO/2 calculations have been performed for several radicals containing C, Si or P. The equilibrium geometries found by the minimization of the total energies and calculated spin densities are compared with results from ESR experiments and INDO calculations. The electronic structure of the radicals is discussed for their equilibrium geometries. 相似文献
50.
Sergei F. Vasilevsky Svetlana V. Klyatskaya Dmitri V. Stass Igor A. Grigir’ev José Elguero 《Tetrahedron letters》2004,45(41):7741-7743
The Stephens-Castro reaction of copper(I) salts of 1-aryl(hetaryl)alkynes with 2,2,5,5-tetramethyl-4-[2-(4-iodophenyl)-vinyl]imidazoline-3-oxide-1-ol proved to be a general method for the preparation of 2,2,5,5-tetramethyl-4-[2-(p-aryl(hetaryl)ethynylphenyl)]vinyl-3-imidazoline-3-oxide-1-oxyles. 相似文献