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91.
Regio- and stereoselective reactions of selenium dihalides with diorganyl diethynyl germanes in CHCl3 afford in yields from preparative to quantitative the first representatives of a new class of selenium–germanium containing heterocycles - 3,6-dihalogen-4,4-diorganyl-1,4-selenagermafulvenes. The reaction of selenium tetrachloride under the same conditions leads to the first representatives of a new class of selenium–germanium containing cyclopentene heterocycles - 2-dichloromethyl-2,4-dichloro-3,3-diorganyl-1-selena-3-germacyclopentenes-4 as well as to the unknown 3,6,6-trichloro-4,4-dialkyl-1,4-selenagermafulvenes formed as a result of a spontaneous dehydrochlorination of the cyclopentene heterocycles. In a case of SeBr4 the process of dehydrobromination is dominating. The structures of the heterocycles were proved by multinuclear (1H, 13C, 77Se) spectroscopy and mass-spectrometry. In the 1H NMR spectra of Z-isomers of 1,4-selenagermafulvenes a long-range spin–spin interaction between exo- and endocyclic olefinic protons through five bonds is revealed lacking in the E-isomers.  相似文献   
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Conclusions In the reaction of methylmagnesium iodide with esters of perfluorocarboxylic acids, the magnesium salt of the hemiketal was found to be more stable and the ketone yield was found to be higher with increasing bulk of the alkoxy group of the ester.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1163–1165, May, 1988.  相似文献   
94.
Conclusions Aminomethylation of mono- and diethynylsilanes has been investigated. Dimethyldiethynylsilane can react at either one or both the ethynyl group positions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2818–2820, December, 1969.  相似文献   
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97.
UV spectroscopic studies combined with kinetic measurements for the Suzuki–Miyaura reaction catalyzed by “ligand-free” catalytic systems have demonstrated that the base is involved in the formation of the palladium complexes ensuring the occurrence of the transmetalation stage. It follows from UV monitoring data for the catalytic reaction involving aryl iodides that a considerable part of palladium during the process is in the form of Pd2+ acid complexes with endogenous anions and does not participate in the main catalytic cycle.  相似文献   
98.
Previously unknown 1,1-diethylnylsilacycloalkanes (CH2)4nSi(C& = CH)2 (n = 3, 4) were prepared by the reaction of HC& = CMgBr with 1,1-dichlorosilacycloalkanes (CH2)4nSiCl2 (n = 3, 4). The reaction of (CH2)4Si(C& = CMgBr)2 with (CH2)4SiCl2 in THF under conditions of high dilution gives cyclo(tetramethylene)- silethynes [(CH2)4SiC& = C]4 with an admixture of cyclodi(tetramethylene)silethyne [(CH2)4SiC& = C]2. The re- action of Me2Si(C& = CSiMe2C& = CMgBr)2 with (CH2)4SiCl2 was used to prepare 1,1,4,4,7,7-hexamethyl-10,10- tetramethylene-1,4,4,10-tetrasilacyclododeca-2,5,8,11-tetrayne.  相似文献   
99.
Hydrochlorides salts of [(alkylamino)alkyl]amides of 1-allyl-4-hydroxy-6,7-dimethoxy-2-oxo-1,2-di-hydroquinoline-3-carboxylic acid were synthesized as potential biologically active compounds. Pharmacological testing showed promise for using these compounds to develop new highly efficient opioid receptor antagonists.  相似文献   
100.
Reactions of acyl iodides R1COI (R1=Me, Ph) with trialkyl(alkynyl)silanes,-germanes, and stannanes (R2C≡CMR 3 3 ; M=Si, Ge, Sn) were studied. Acyl iodides reacted with the germanium and tin derivatives with cleavage of the M-Csp bond and formation of the corresponding trialkyl(iodo)germanes and-stannanes R 3 3 MI (M=Ge, Sn) and alkynyl ketones R1C(O)C≡CR2 and R1C(O)C≡CC(O)R1. By contrast, the reaction of acetyl iodide with ethynyl(trimethyl)silane gave only a small amount of 1,2-diiodovinyl(trimethyl) silance as a result of iodine addition at the triple bond. Bis(trimethylsilyl)ethyne failed to react with acetyl iodide.  相似文献   
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