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991.
I. V. Katal'nikov V. A. Kuz'min P. P. Levin K. de Jonge G. R. Myul'man 《Russian Chemical Bulletin》1989,38(8):1758-1760
The spectrokinetic indices of the triplet states of nitroaromatic amides were established. The quenching of triplet states by tertiary aromatic amines in apolar solvents leads to the formation of triplet exciplexes. A charge transfer state makes the major contribution to the structure of these exciplexes. Hydrogen atom transfer proceeds efficiently in the case of secondary aromatic amines, leading to the formation of the corresponding neutral radicals.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1912–1915, August, 1989. 相似文献
992.
993.
É. Ya. Lukevits A. E. Pestunovich M. G. Voronkov T. M. Kupch 《Chemistry of Heterocyclic Compounds》1972,8(4):442-444
It was found that the hydrosilylation of N-allylpyrrolidine and N-allylpiperidlne by trialkylsilanes, triethoxysilane, and 3H-heptamethyltrisiloxane in the presence of H2PtCl6 · 6H2O proceeds to form -adducts.Communication XXXII from the series Nitrogen-Containing Organosilicon Compounds. See [1] for communication XXXI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 485–487, April, 1972. 相似文献
994.
Saturated and benzylic organomagnesium compounds are shown to readily undergo addition reactions with the conjugated enynes HCHCH2R′, with R′ = alkyl, OH, OC4H9, NHC25, N(C2H5)2, by refluxing for several hours in benzene or toluene.This reaction leads to both υ-acetylenic compounds (1,2-addition) and β-allenic compounds (1,4-addition). 相似文献
995.
996.
997.
998.
999.
Synthesis of 1,7-bis(4′-aminophenylamido)-m-carborane and 1,7-bis(4′-aminophenylcarboxy)-m-carborane
V. V. Korshak L. G. Komarova N. G. Komarova V. V. Vagin G. A. Kats 《Russian Chemical Bulletin》1986,35(12):2554-2555
Conclusion 1,7-Bis(4-aminophenylamido)- and l,7-bis(4-aminophenylcarboxy)-m-carboranes were prepared and characterized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2786–2787, December, 1986. 相似文献
1000.
The nickel dithiophosphates and their corresponding disulphides are shown to be more effective uv stabilisers for LDPE than the closely related nickel xanthates and disulphides (dixanthogens). In general, the nickel complexes in both series are more effective uv stabilisers than the disulphides.Evidence is presented to show that the better performance of the dithiophosphates than the xanthates is associated with their higher solubility in the polymer. For the same reason, nickel dithiolates containing long alkyl substituents are more effective uv stabilisers than those containing shorter alkyl substituents.Thermal processing adversely affects the photo-stabilising performance of nickel dithiolates whereas the performance of the less efficient disulphides is enhanced under the same conditions. In the former case, the uv stability of the polymer is shown to be directly proportional to the amount of the nickel complex left after processing. In the case of the disulphides, on the other hand, the evidence suggests that increasing the severity of their processing increases the extent of oxidation to products which are more effective uv stabilisers than the parent disulphides. 相似文献