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1.
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
2.
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
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.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
11.
Long-liied (τ > 10?3 s), electronically-excited (E * > 4 eV) neutral metastables, whose formation was attributed to the presence of SO2, were observed in the three titled systems. Their possible identity as collisionally-accessed metastable states of the normal , cyclic , or superoxide isomers of SO2 is discussed. 相似文献
12.
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
13.
The occurrence of the (py2H)+ ion in solutions containing pyridinium ion and pyridine has been established spectroscopically.The infrared and Raman spectra of the four species , , , and have been examined in the range 80–6000 cm?1. The spectra are independent of concentration, solvent, or counterion if this is inert. The NH stretching band is a strong, broad doublet with maxima at 2080 and 2530 cm?1. In the bridge deuterated species there is a single strong, broad, ND stretching band, maximum at 1920 cm?1. The N-N stretching is infrared active, at ~138 cm?1. The internal modes of the base are all singlets in both the infrared and Raman spectra. The proton bridge is between the σ orbitais on the N atoms. 相似文献
14.
It is suggested that while evaluating contact charge densities from internal conversion coefficients it is important to consider overlap effects. Ratios of the internal conversion coefficients and are evaluated as a function of interatomic separation for Fe3+ in an octahedral arrangement of Br? ions. 相似文献
15.
Peter Scharfenberg 《Chemical physics letters》1981,79(1):115-117
The energy profile?(x) of minimum energy paths, , is analyzed and analytical formulae for reduced forces d?/dx as well as reduced force constants d2?/dx2 are derived which allow a unique classification of critical points regarding the potential hypersurface . 相似文献
16.
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
17.
Substituted vanadium carbonyl compounds with η2-bonded acyl ligands (η2-RCO)V(CO)3 ( = ditertiary phosphines or arsines: dppe, dppp, dppm, diars, arphos, dpase) have been prepared by photochemical reaction of [V(CO)4] with various substituted benzoyl chlorides and cyclopropanylcarbonyl chloride.Effects of aromatic substituents and upon the thermal stability of the η2-acylcarbonylvanadium compounds are discussed. IR ν(CO) force constants and 51V NMR signals are linearly correlated with Hammett's σ constants of the aromatic substituents.The preparation of V(CO)2Cl(diars)2 is described. 相似文献
18.
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
19.
Electrokinetic phenomena in porous membranes were studied in the framework of the linear thermodynamics of irreversible processes. Phenomenological coefficients of two commercial porous membranes were determined. The variation of these coefficients with the different concentrations of NaCl used was also studied. Onsager's reciprocal relationship between cross-coefficients holds within the limits of experimental error.Membrane potentials were measured at concentrations ranging from 10?3M to 75 X 10?3M. The apparent transport number of the cation, , was calculated from the diffusion potential expression. An electrometric method was used to obtain the true cation transport number, , and the water transport number, , for different solution concentrations, ranging from 15 x 10?3M to 75 x 10?3M. The true transport number of the cation, , was also determined, taking into account water transport across the membrane. A good agreement was found between and values. 相似文献
20.
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