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1.
Conclusions Methylselenophosphonium salts have been obtained for the first time by the reaction of full amides of phosphoroselenoic and alkylphosphonoselenoic acids with methyl iodide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, p. 169, January, 1969.  相似文献   

2.
The synthesis and mechanism of formation of phosphonium salts of the type [R3P+CFXY]Z? (where X = F, Cl, Br; Y = Br, Cl; Z = Br, Cl), bis-phosphonium salts of the type [R3P+CF2P+R3]2Br?, and phosphoranium salts of the type [R3P+C?FP+R3]X? (X = Br, Cl) will be presented. The applicability of these substrates in the generation of useful nucleophilic or electrophilic synthetic intermediates will be discussed.  相似文献   

3.
4.
Pyridinium salts     
New 4- (benzazol-2-yl)pyridinium salts have been synthesized. Their reduction in a neutral medium with sodium tetrahydroborate has given 2-(1,2,5,6-tetrahydropyridin-4-yl)benzazoles. The catalytic hydrogenation of the latter leads to piperidine derivatives which have also been synthesized by an independent route.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 104–107, January, 1974.  相似文献   

5.
A new method was developed for the synthesis of dioxolanium salts by the condensation of 1,2-glycols of the pinacol series with aliphatic acid anhydrides in the presence of perchloric acid. The dioxolanium ring is opened to form monoacylates of the starting pinacols under the influence of water, alcohol, and ammonia. A method was developed for the acetylation of aromatic compounds by dioxolanium salts.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1023–1026, August, 1971.  相似文献   

6.
Stable aziridiniminium salts have been obtained from the reaction of 2-amino-1-azirines with trityl tetrafluoroborate or trimethylsilyl triflate. These new derivatives of α-lactams react with carbanions to give 2-amino-1-aziridines.  相似文献   

7.
8.
The catalytic acylation and subsequent heterocyclization of- and-acetonyl derivatives of thiophene were studied. Mechanisms for the synthesis of thienopyrylium salts, the reaction of which with ammonia leads to the difficult-to-obtain thienopyridines, are proposed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 320–325, March, 1971.  相似文献   

9.
The reaction of pyrylium salts having a free or position with triphenylphosphine has given pyranylphosphonium salts. 2,4,6-Trisubstituted pyrylium salts do not react with triphenylphosphine. The properties and IR spectra of the compounds synthesized are discussed.  相似文献   

10.
Conclusions Dialkyldialkoxyphosphonium halides are stable only in the case of branched alkoxy groups. The stability is explained by the difficulty of attack of the isoalkoxy group by halide anions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 415–417, February, 1971.  相似文献   

11.
The synthesis and properties of a new class of inorganic salts, named pentafluorosulfanylnitramide salts (or pentafluorosulfanylnitraminic acid salts) [Z+SF5NNO2-], are described. A number of SF5-nitramide salts (Z+SF5NNO2-) were successfully prepared via nucleophilic displacements from carbamates and/or ion exchange techniques, but some salts [M(SF5NNO2)x; M = Li, Mg, Al] decomposed during isolation procedures and appear to be unstable in the solid state. Single-crystal X-ray diffraction was used to fully characterize the Z+SF5NNO2-, and their properties/structures are compared with those of the corresponding dinitramide salts (or dinitraminic acid salts), Z+N(NO2)2-. X-ray crystallography revealed major structural differences between N(NO2)2- and SF5N(NO2)- salts concerning the N-N distances and the angles subtended at the central nitrogen atom. In the N(NO2)2- salts, there are two nonequivalent N-N (average lengths 1.372(2) and 1.354(2) A) distances and an average N-N-N angle of 115.8(3) degrees (falls between sp3 and sp2 hybridization). In the SFsNNO2- salts, the average N-N distance is much shorter, 1.308(9) A, and the average N-N-S angle is 120.0(5) degrees (closely fits sp2 hybridization). The SF5NNO2- salts show a remarkable metrical similarity for the SF5 moiety in all structures, indicating a lack of sensitivity to its steric and electronic environment. This is in marked contrast to N(NO2)2-, where there is a wide variation in conformations adopted by these anions which can be related to their environment.  相似文献   

12.
A number of mono-amino-functionalised ferrocenes, ferrocene salts and a mono-amino-functionalised ferrocenium salt have been synthesised and characterised. This represents a novel method of accessing these important classes of molecules. In the cases of some of the ferrocene salts, there are some interesting structural features in the solid state. These include N-H...O and N-H...F hydrogen bonds.  相似文献   

13.
The synthesis of berberine analogs — substituted dibenzo[a,g]quinolizinium salts — was worked out on the basis of 2-benzopyrylium salts.See [1] for communication XXII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1481–1483, November, 1977.  相似文献   

14.
Three new methods have been proposed for the synthesis of 3-bromopyrylium salts. An unsaturated 1,5-diketone is converted into a 3-bromopyrylium salt by allyl bromination and the addition of bromine to the double bond. 3-Bromopyrone, obtained by the bromination of dibenzoylacetone is converted by treatment with Grignard reagents into 3-bromopyrylium salts. Similar compounds have also been synthesized by the pyrylation of aromatic and heterocyclic compounds with 3-bromo-4-chloropyrylium salts obtained from 3-bromopyrone.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 873–877, July, 1973.  相似文献   

15.
The previously unknown bis-2-benzopyrylium salts and 2-benzopyrylium salts containing an alkylcarboxy group were synthesized by the acylation of some alkoxy-substituted deoxybenzoins and phenylacetones with dibasic aliphatic acids in polyphosphoric acid. The effect of the structure of the dicarboxylic acid on the structure of the reaction products was followed. The IR spectra of the synthesized salts are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 454–456, April, 1972.See [8] for communication XI.  相似文献   

16.
2-Veratryl-5,6-dimethoxyindanone and 2-veratrylindane-1,3-dione, respectively, were obtained by intramolecular acylation ofα,β-diveratrylpropionic acid and condensation of veratraldehyde with phthalide in strongly alkaline media. A method was worked out for the synthesis of indeno[1,2-c]-2-benzopyrylium salts, from which indeno[1,2-c]isoquinolines are formed in good yields.  相似文献   

17.
The previously unknown 2,4,6-trisubstituted pyrylium salts 1-4 , carrying cyclopropyl and methyl or phenyl substituents in the same molecule, and 5-8 , substituted with isopropyl groups instead of cyclopropyl, were synthesized as perchlorates. The electronic spectra and the C-13 nmr spectra of the two groups of compounds were compared. A cyclopropyl group has a batochromic effect on the electronic spectrum roughly half that exerted by a phenyl; replacement of an alkyl by a cyclopropyl shifts the highest wavelength absorption band by about 20 nm. Presence of phenyl substituents reduces the batochromic effects of cyclopropyl substituents. The effects of both cyclopropyl and phenyl substituents on the electronic spectra are smaller for pyrylium than for tropylium. The nmr signals for all the ring carbons are shifted upfield upon replacement of isopropyl by cyclopropyl; in particular, the effect of substituents in position 2 upon the chemical shift of C(4) indicates that the electron-releasing effect varies in the series alkyl < phenyl < cyclopropyl, in agreement with the findings for 2,6-disubstituted pyrylium salts. The difference between the chemical shifts for the methine and methylene carbons of the three-membered ring is a function of the electron demand of the cationic heterocycle.  相似文献   

18.
19.
20.
Furfural 4-nitrosemicarbazone potassium and sodium salts were synthesized. The structures of these compounds were studied by IR and NMR spectroscopy and X-ray diffraction. The computer screening with the PASS program revealed higher biological activity of the salts compared to the starting furfural 4-nitrosemicarbazone.  相似文献   

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