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1.
A. F. Khlebnikov M. S. Novikov A. A. Bespokoev R. R. Kostikov J. Kopf Z. A. Starikova M. Yu. Antipin 《Russian Journal of Organic Chemistry》2005,41(6):922-932
Rhodium acetate-catalyzed decomposition of methyl 2-diazo-2-phenylacetate in the presence of substituted N-methylbenzylideneamines possessing an activated alkenyl fragment (dipolarophile) in the side chain gives products of intramolecular cycloaddition of intermediate Z,E- and E,Z-azomethine ylides. The cycloaddition is regioselective, and the products are hexahydrochromeno[4,3-b]pyrrole derivatives. The stereoselectivity of the process depends on the temperature. In the temperature range from 20 to 80°C, the major stereoisomer is that with cis junction of the tetrahydropyran and pyrrolidine rings. N-Phenylazomethine ylides generated from methyl 2-diazo-2-phenylacetate and alkyl 4-[2-(phenyliminomethyl)phenoxy]-2-butenoates at 40°C undergo cyclization to aziridines at a higher rate, as compared to the rate of cycloaddition to the internal dipolarophile. N-Phenylazomethine ylides generated by thermolysis of the corresponding aziridine or by the “deprotonation” method react with equal regio- and stereoselectivity to give intramolecular cycloaddition products, hexahydrochromeno[4,3-b]pyrrole derivatives with trans-fused tetrahydropyran and pyrrolidine rings. Analysis of the experimental and calculation data suggests preference of the endo transition state in the cycloaddition of the examined azomethine ylides.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 939–949.Original Russian Text Copyright © 2005 by Khlebnikov, Novikov, Bespokoev, Kostikov, Kopf, Starikova, Antipin. 相似文献
2.
A computational study has been performed to investigate the mechanism of RhIII‐catalyzed C−H bond activation using sulfoxonium ylides as a carbene precursor. The stepwise and concerted activation modes for sulfoxonium ylides were investigated. Detailed theoretical results showed that the favored stepwise pathway involves C−H bond activation, carbonization, carbene insertion, and protonation. The free energy profiles for dialkylation of 2‐phenylpyridine were also calculated to account for the low yield of this reaction. Furthermore, the substituent effect was elucidated by comparing the energy barriers for the protonation of meta‐ and para‐substituted sulfoxonium ylides calculated by density functional theory. 相似文献
3.
Borisova I. V. Nechaev M. S. Khrustalev V. N. Zemlyanskii N. N. Ustynyuk Yu. A. 《Russian Chemical Bulletin》2002,51(5):721-753
The review surveys the data on the reactions of phosphorus and arsenic ylides with compounds containing E=X bonds (E = C, Si, Ge, or Sn; X = C or S), cyclic oligomers (R2ES)n (n = 2 or 3), and heavier analogs of carbenes. These reactions give rise to two new classes of heteroorganic betaines containing the (+)E15—C—E14—X(–) (I) and (+)E15—C—E14(–) (II) (E15 = P or As; E14 = Si, Ge, or Sn; X = C or S) structural fragments. Procedures for the synthesis of these compounds, their reactivities, the X-ray diffraction structures, and the electronic structures established by high-level quantum-chemical calculations are considered in detail. The carbon analogs of betaines of type I, viz., compounds bearing the (+)P—C—C—X(–) fragment (III), are also discussed. The latter were long considered as possible intermediates in the reactions of compounds containing the polar C=X bond (X = C, O, S, NR, etc.) with phosphorus ylides (classical Wittig and Corey—Chaykovsky reactions and related processes). 相似文献
4.
O. I. Kolodyazhnyi 《Russian Journal of General Chemistry》2005,75(7):1017-1039
Results of the research into ylides containing fluorine atoms on the phosphorus atom of the P=C group are summarized. These compounds are convenient reagents for preparing various organic and organo-phosphorus compounds hardly available by other methods. Main synthetic routes to P-fluoroylides are considered. Chemical and physical properties of the ylides are reviewed. The peculiar chemistry of these compounds is shown, that significantly differs from the chemistry of triphenylphosphonium ylides. Prospective synthetic applications of P-fluoroylides are analyzed.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 7, 2005, pp. 1076–1099.Original Russian Text Copyright © 2005 by Kolodyazhnyi. 相似文献
5.
A. F. Khlebnikov I. V. Voznyi M. S. Novikov R. R. Kostikov 《Russian Journal of Organic Chemistry》2005,41(4):560-566
Geminal dichloroazomethine ylides generated by reaction of dichlorocarbene with Schiff bases derived from O-alkenyl- or O-alkynylsalicylaldehyde undergo intramolecular [3 + 2]-cycloaddition with participation of the olefinic or acetylenic dipolarophile to afford chromeno[4,3-b]pyrrole and chromeno[4,3-b]pyridine derivatives. The greatest yields of the intramolecular cycloaddition products were obtained from N-methyl-substituted dichloroazomethine ylides, whereas the main stabilization path of N-phenyl and N-tert-butyl derivatives was cyclization to geminal dichloroaziridines.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 4, 2005, pp. 571–577.Original Russian Text Copyright © 2005 by Khlebnikov, Voznyi, Novikov, Kostikov. 相似文献
6.
R. R. Kostikov A. P. Molchanov S. V. Amosova B. A. Trofimov 《Russian Chemical Bulletin》1980,29(6):971-975
Conclusions The reaction of dihalocarbenes with vinyl sulfides gave gem-dihalocyclopropyl sulfides. The relative activity of the sulfides toward dichlorocarbene is 5–6 times greater than that of the corresponding ethers. The theory was expressed that intermediate sulfur ylides are formed in the given reaction.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1354–1358, June, 1980. 相似文献
7.
The interaction of iron carbonyls Fe
n
(CO)
m
(wheren = 1,m = 5;n = 2,m = 9;n = 3,m = 12) with anionic Lewis bases (H–, F–, Cl–, Br– , I–, CN–, SCN–, N3
–, MeSO3
–, MeCO2
–, CF3CO2
–, S2
–, CO3
2–, and SO4
2–) passes through two-stage redox-disproportionation. The first stage is the formation of an iron carbonyl-base complex, [Fe
n
(CO)
m–1C(O)L]–, and the second is a single-electron reduction of this complex by another molecule of the initial iron carbonyl, giving rise to Fe(l) and Fe(–l) derivatives.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 248–249, January, 1996. 相似文献
8.
A convenient and facile one-pot synthesis of stable phosphorus ylides and 1,4-diionic organophosphorus compounds is reported by the reaction of triphenylphosphine,dialkylacetylenedicarboxylates and N-H,C-H or S-H acids in the presence of polyethyleneglycol (PEG),β-cyclodextrin(β-CD),glycerine(Gly) or ethyleneglycol(EG) in water.This methodology is of interest due to the use of water as a solvent,thus minimizing the cost operational hazards,and environmental pollution. 相似文献
9.
The intramolecular cyclization of keto-stabilized sulfonium ylides obtained from β-alanine and containing various imide fragments
was studied. On heating in toluene in the presence of PhCO2H, ylides containing a phthalimide moiety are converted into indolizidine-2,6-dione derivatives, whereas those incorporating
a 4-methyl-1,2,3,6-tetrahydrophthalimide or pyrrolidine-2,5-dione moieties do not undergo cyclization.
For Part 6, see Ref. 1
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2008–2012, November, 1997. 相似文献
10.
Vapor-phase reactions ofn-pentan-1-ol with 2-ethylhexyiamine and ofn-heptan-1-ol with cyclohexylamine occurring in the presence of an industrial oxide copper-zinc-aluminum catalyst SNM-1 at 175–185°C have been found to afford the corresponding asymmetric secondary and tertiary amines in yields of 59–99 % and 5–49 %, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 799–800, April, 1993. 相似文献
11.
Enrique J. Baran 《Monatshefte für Chemie / Chemical Monthly》1979,110(2):297-300
Mean amplitudes of vibration for various octahedral complex compounds of the typeLnCl6
3– andLnBr6
3– (withLn=Nd, Eu, Gd, Dy, Er, and Yb) have been calculated, at different temperatures, using known spectroscopic data. The results are briefly discussed and it is found that theLn–Cl andLn–Br amplitude values are highly characteristic. 相似文献
12.
A. M. Shestopalov I. A. Aitov Yu. A. Sharanin V. P. Litvinov 《Russian Chemical Bulletin》1991,40(6):1271-1278
The reactions of pyridinium, picolinium, and quinolinium salts and ylides with tetracyanoethylene have been found to be regioselective. Reaction of azinium salts with tetracyanoethylene in aqueous methanol affords azinium tricyanoethylenolates, but pyridinium ylides react differently, with the highly stereo-selective formation of the Z-isomers of 3-aroyl-3-(R-1-pyridinio)-1,1,2-tricyano-2-propen-1-ides, which are 1,4-ylides with maximum charge separation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1431–1439, June, 1991. 相似文献
13.
Zusammenfassung Es wird die Bildung von stabilen Sulfoniumyliden aus Sulfoxiden und genügend stark C–H-aciden Verbindungen beschrieben.
Herrn Prof. Dr.A. Wacek zum 70. Geburtstag in alter Freundschaft! 相似文献
The formation of stable sulphonium ylides from sulfoxides and sufficiently strong C–H-acidic compounds is described.
Herrn Prof. Dr.A. Wacek zum 70. Geburtstag in alter Freundschaft! 相似文献
14.
The literature on the use of sulfur ylides in the synthesis of heterocyclic systems of varied structure is reviewed. The possible preparative value of these reactions is discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 147–173, February, 1990. 相似文献
15.
M. S. Novikov A. F. Khlebnikov M. A. Egarmin J. Kopf R. R. Kostikov 《Russian Journal of Organic Chemistry》2004,40(10):1493-1499
Azomethine ylides generated by reaction of difluorocarbene with N-alkyl- and N-arylimines derived from benzaldehyde and benzophenone react with N-benzylidenebenzenesulfonamide in a regioselective fashion, yielding the corresponding imidazolidin-4-ones via 1,3-dipolar cycloaddition at the C=N bond. Ylides generated from benzaldehyde imines give rise to mixtures of stereoisomeric 2,5-diphenyl-1-(phenylsulfonyl)-imidazolidin-4-ones, the cis isomer prevailing.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1542–1548.Original Russian Text Copyright © 2004 by Novikov, Khlebnikov, Egarmin, Kopf, Kostikov. 相似文献
16.
The carbonylation of acetaldehyde to give butyl lactate has been carried out in the presence of rhodium and cobalt compounds atP
CO=5–9 MPa andT=383–483 K.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 570–571, March, 1995. 相似文献
17.
S. N. Lakeev F. Z. Galin L. M. Khalilov G. A. Tolstikov 《Russian Chemical Bulletin》1992,41(3):566-570
Some reactions of phthalimide-containing keto-stabilized sulfur ylides have been investigated. It was established that in addition to the formation of the usual products for keto-stabilized sulfur ylides, the reaction with acrylonitrile is accompanied by a rearrangement and leads to 1,1-disubstituted cyclopropanes.Institute of Chemistry, Bashkir Science Center, Urals Branch, Russian Academy of Sciences, 450054 Ufa. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 720–726, March, 1992. 相似文献
18.
The transient kinetics of the loss of electrons generated by light pulses in powdered AgCl has been studied by the microwave photoconductivity method (36 GHz) at 295 K. At high light intensities,I
0 > 1014 photon cm–2 per pulse, the kinetics obeys the second-order law. The rate constant of the recombination of free electrons and holes is equal to 2·10–12 cm3 s–1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2234–2236, September, 1996. 相似文献
19.
M. S. Novikov A. F. Khlebnikov I. V. Voznyi O. V. Besedina R. R. Kostikov 《Russian Journal of Organic Chemistry》2005,41(3):361-369
N-Alkyl- and N-arylimines derived from o-allyl-, o-allyloxy-, and o-(2-propynyloxy)arenecarbaldehydes react with difluorocarbene to give indeno[1,2-b]pyrrole and chromeno[4,3-b]pyrrole derivatives. The reaction involves intermediate formation of difluoro-substituted azomethine ylides which undergo regio- and stereoselective intramolecular ring closure at the multiple bond.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 3, 2005, pp. 372–380.Original Russian Text Copyright © 2005 by Novikov, Khlebnikov, Voznyi, Besedina, Kostikov.Dedicated to Full Member of the Russian Academy of Sciences V.I. Minkin on his 70th Anniversary 相似文献
20.
A. A. Murav'ev S. V. Pribysh Yu. P. Baidarovtsev V. S. Savost'yanov A. N. Ponomarev 《Russian Chemical Bulletin》1994,43(5):809-811
The electrophysical characteristics of metallopolymers obtained by spontaneous polymerization of complexes of Er, Ca, and UO2 nitrates with acrylamide were investigated. The conductivity () at direct current was measured (10–5 to 10–6 Ohm–1 cm–1), and its alterations during the polymerization were observed. The conductivity of the metallopolymers obtained depends essentially on the voltage applied during the polymerization and the component ratio in the original mixture. It is concluded that the conductivity is ionic in character. The conductivity and the electret properties discovered depend on the moisture content of the samples.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 865–867, May, 1994. 相似文献