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1.
François Mathey 《Tetrahedron letters》1979,20(20):1753-1756
1-Benzyl-3,4-dimethylphosphate - is converted into 2-phenyl-4,5-dimethyl-λ3-phosphorin - through 1,2-dihydro-λ5-phosphorines and . 相似文献
2.
Pyrolysis of diacetate produced 3 major products, –. The most reasonable pathway to these products, supported by deuterium labelling studies, is via double bridgehead olefins and . 相似文献
3.
J.W.F.L. Seetz F.A. Hartog H.P. Böhm C. Blomberg O.S. Akkerman F. Bickelhaupt 《Tetrahedron letters》1982,23(14):1497-1500
Careful addition of 1,3-dibromopropane to magnesium in Et2O yields 1,3-bis(bromomagnesio)propane which is purified via “magnesacyclobutane” . Reactions of with H2O, CO2, HgBr2 and Me3SnCl are reported. MgBr2 catalyses the decomposition of to allylmagnesium bromide . 相似文献
4.
The cyclometallated monohydrides (R H or Me) react with NaOPri/PriOH/H2 to give fluxional tetrahydrides, probably . These are highly fluxional having magnetically equivalent hydridic hydrogens, even at ---100°C. When treated with HBr, , gives and with CO it gives a mixture of complexes which are probably (2 isomers) and . When treated with ButNC this tetrahydride undergoes similar reactions but another (major) product is formed which appears to be binuclear and fluxional and is probably of type , with four bridging hydrogens. 相似文献
5.
D-Ring aromatic steroid ( having 19-methyl and C6-nitro group has been stereo-selectively synthesised by an intramolecular cycloaddition of the -quinodimethane () derived thermally from 5-acetoxy-2-[2-(1-cyano-4-methoxybenzocyclobutenyl)-1-nitroethyl]-1-ethenyl-1-methylcyclohexane (). 相似文献
6.
Kimiak Yamamura Kazumi Nakatsu Kenji Nakao Tomoo Nakazawa Ichiro Murata 《Tetrahedron letters》1979,20(52):4999-5002
A series of o-tropyliobiphenyl tetradfluoroborates has been synthesized. Evidences are presented to show that exhibit strong intramolecular charge-transfer interaction between tropylium ion and remote aryl ring. The structure of was determined by single crystal X-ray diffraction study. 相似文献
7.
A.V. Fokin 《Journal of fluorine chemistry》1980,16(6):565-566
Chlorine fluorosulfonate adds exceptionally easy not only to various alkenes, perfluorobenzene, but to alkynes too The addition of peroxydisulfuryldifluoride to alkyl- and perfluoroalkyliodides leads to unstable adducts, which decompose with the formation of alkylfluorosulfonates and iodine fluorosulfonate; the latter was trapped with fluoroalkenes The use of ClOSO2F allows to substitute selectively for the fluorosulfonate group the chlorine atom in monochloroacetic acid esters as well as the fluorine atom in hexafluoroacetone N-fluoroimine ClOSO2F serves as an exceptionally active chlorinating reagent for fluorinated alcohols, nitrosocompounds, perfluoroacid amides and particularly for benzene The reaction of (OSO2F)2 with perfluoroacid amides leads to the corresponding N,N-bis(fluorosulfonate)amides, which easily rearrange into alkylfluorosulfonates The hypochlorites of fluorinated alcohols are stable enough and they, similarly to ClOSO2F, are able to add to alkenes, fluoroalkenes (but not to perfluoroisobutylene), bis(trifluoromethyl)ketene, trifluoromethylisocyanate and perfluoronitriles The fluorosulfonatoacetic acid esters are unstable at the ambient temperature, but they can be widely used in situ as a very effective alkylating reagents 相似文献
8.
Nikolai S. Zefirov A.S. Kozmin V.V. Zhdankin V.N. Kirin I.V. Bodrikov B.B. Sedov V.G. Rau 《Tetrahedron letters》1979,20(37):3533-3536
“doping-addition” of 2-NO2C6H4SCl to the tricyclo[4,2,2,02,5]deca-3,7,9-triene system occurs to give unusual products: (i) rearranged caged cyclopropane and (ii) the stable cross-perchlorate . 相似文献
9.
Product study and kinetic data of the solvolysis of the bridgehead chlorides () and ( indicate the neighboring group participation of the strained bridgehead double bonds. 相似文献
10.
The stereoselective fluorination of four couples of diastereoisomeric 2-alkyl 3-hydroxy 3-phenylpropanoic methyl esters by the reaction of the phenyltetrafluorophosphorane with the corresponding trimethylsilylethers derivatives is described. The structure of the 2-alkyl 3-fluoro 3-phenyl propanoic methyl esters obtained quantitativly has been determined unambiguously by NMR analysis. 19F NMR results permit us to determine the relative populations of the rotamers for each of the isomers threo and erythro. 相似文献
11.
J. Carre M. Kollmannsberger J. Thourey G. Perachon J. Bousquet 《Journal of fluorine chemistry》1976,8(5):401-408
The standard enthalpy of formation of tellurium tetrafluoride has been determined: by combustion in fluorine: by reaction in a normal solution of soda: 相似文献
12.
Philippe Fornier de Violet Roland Bonneau Jacques Joussot-Dubien 《Chemical physics letters》1974,28(4):569-572
The laser flash photolysis of iodine-iodide mixtures in alcoholic solvents produces transient species absorbing in the red and near infrared region with maxima at 740 and 590 nm. The 740 nm absorption band has already been attributed to the well known I ion. In this work the 590 nm absorption band is assigned to the I radical anion which presumably could be formed by the equilibrium reaction: I + I3- ? I. The variations of the intensities of the 590 and 740 nm transient absorption bands as a function of I3? concentration, temperature and solvent, support this assignment. The kinetics of formation of I and I has been studied in solutions of tertiary butanol. An analysis of the experimental results shows that the I ion could be formed via a mechanism involving an I intermediate. 相似文献
13.
Reduction of α,β-unsaturated iminium salts by 3,5-dicarbethoxy-2,6-dimethyl-1,4-dihydropyridine results in or (primary) reduction products, depending on the basicity of the amine component. 相似文献
14.
Aziridines and 2H-azirines are now very easy to prepare. These small rings are transformed in fluoroamine and fluoroketone by reaction with HF liquid or Olah reagent. Different compounds , or are obtained. A lot of examples will be described.a) Configuration of depends of the reagent (HF liquid or Olah reagent): Mechanism of this reaction will be discuss.b) Some aziridines give a mixture of fluoroaminoisomers. Example: With R = H, a mixture of (65 %) and (35 %) is obtained. It is possible to form quantitatively one regioisomer only, by using activating group on the nitrogen (R CO2tBu).c) From azirine , formation of or dépends of the nature of substituents at carbon C-2. If a carbocation can be easily formed at C-2 carbon, only fluoroketone is isolated.Difluoroamine are obtained if carbon C-2 is a secondary or primary one. By using a modified Olah's reagent, we improve the yield.Application of this results on synthesis of fluorosteroïd compound will be presented: 相似文献
15.
J.A. Connor 《Journal of organometallic chemistry》1978,144(3):C58-C62
The formation of newintermediates and especially germaimines R2GeNR′ has been observed in the reaction of germylenes with phenyl azide (precursor of phenylnitrene). These transient derivatives lead, by polycondensation reactions, to the corresponding cyclic or linear germazanes , and are characterized by insertion reactions into the germanium—nitrogen bond, cleavage and addition reaction with tetrahydrofuran, and pseudo-Wittig reactions with benzaldehyde. The latter produces the corresponding germoxanes via new intermediates and phenyl benzaldimine. 相似文献
16.
The reaction of an aromatic lithium reagent, LiR, with a perfluoroacid anhydride (RfCO)2O, in ether solution at low temperatures, produces esters of composition in addition to the expected ketone . Mixed esters of composition may be prepared by starting with a ketone and reacting with a lithium reagent LiR followed by perfluoroacid anhyride (RfCO2O. Hydrolysis of the esters provide a convenient route to trertiary alcohols of composition Rf(R) 2COH. 相似文献
17.
Di-t-butylzinc adds easily to conjugated enynes . Only the acetylenic bond is involved in this reaction which proceeds via trans-addition. This regioselective and stereoselective addition leads to conjugated dienes . 相似文献
18.
In the electron transfer between the cation radicals of the amine moiety of four intramolecular anthra cene-amine systems and the anion radicals BXXX of some heterocyclic and carbonyl compounds in acetonitrile/toluene, the triplet state of the anthracene moiety is formed. As intermediates in this process, intramolecular and intermolecular triplet exciplexcs or and or are discussed. 相似文献
19.
The kinetics of oxidation of amino acids (AA) by peroxomonosulphate (PMS) in the presence and absence of formaldehyde were studied. Analysis of the results shows that the rate can be represented as, at constant [H+]and in the absence of formaldehyde In the presence of formaldehyde and at constant [H+]the rate law is Perusal of the kinetic results show that the formaldehyde catalysed reaction occurs 105 times faster than uncatalysed and this is attributed to the formation of Schiff base. Mechanism of the reaction is discussed in terms of kinetic results. 相似文献
20.
Egon Fahr Monika J. Richter Wolfgang Schmitt-Sody Rainer Elbert 《Tetrahedron letters》1980,21(34):3269-3272
Amino-azimines of type (1) react at room temperature with bases (ammonia, aliphatic amines, hydrazine and methyl-hydrazine, aqueous/ethanolic sodium hydroxide) by cleavage of the to the and the NNN moieties (azide). 相似文献