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The paramagnetic susceptibility of Ru(III) in tris-ethylenediamine salts has been measured as a function of temperature. In all cases the iodide salt exhibits a greater susceptibility than the bromide salt. This difference may be attributed to a larger degree of temperature independent paramagnetism in the iodide complex due to the presence of low lying charge transfer states.  相似文献   

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Sulfines react with sulfinyl chlorides giving α-chloroalkyl alkanethiosulfonate esters and with thionyl chloride giving α-chloroalkanesulfenyl chlorides, both in good yields.  相似文献   

5.
Fluxional poly(pyrazolyl)borate complexes of copper and silver, including the carbonyl Cu(CO)B(pz)4, contain coordinated and free pyrazolyl groups, which interchange rapidly on the NMR time scale at room temperature; low temperature limiting spectra can be obtained for some copper complexes at ?100°.  相似文献   

6.
Hydrogenation of propene and other substrates has been studied in flow and batch reactors using various rhodium catalysts. The results show that in some cases rhodium metal is probably formed, but only if solvent is present. A possible explanation is given.  相似文献   

7.
Silver(III) has a half-life at pH 11 of several hundred seconds in aqueous solutions in the presence of 0.1–1.0 M concentrations of certain basic oxoanions (Oxo) (phosphate, carbonate, borate, pyrophosphate, and arsenate). This compares with a lifetime of a few seconds at pH 11 in the absence of these oxoanions. UV-visible spectra and kinetic data for these solutions are interpreted as evidence for the following equilibria in the pH range 9–13.Ag(OH)4?1 + H2O ? Ag(OH)3H2O + OH? (1)Ag(OH)4?1 + Oxo ? Ag(OH)3Oxo + OH? (2)Ag(OH)3Oxo + H2O ? Ag(OH)2(Oxo)H2O + OH? (3) Values of K3 lie in the range 10?3 < K3 <104 M for the systems studied. K2 is estimated to be ~102 for phosphate and slightly smaller for the other systems. Ag(OH)4? undergoes an unusual reaction with pyrophosphate at pH ~ 8 to form a novel silver(II) complex, [Ag(P2O7)2]6?, for which EPR and electronic absorption spectral parameters are reported.  相似文献   

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The conversion of aliphatic alcohols into cyanomethyl ethers via treatment of methyl sulfoxymethyl ethers with trimethylsilyl cyanide - zinc iodide is described.  相似文献   

10.
The bicyclic enone 6 was converted into the adduct 13 by photochemical addition of aliene, and then elaborated through a fragmentation sequence into the -methylene ketone 17.  相似文献   

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3-Lithio 1-trimethylsilyl-1-methoxy allene 4 reacts with aldehydes to give adducts that are readily transformed into 2-trimethylsilyl furans.  相似文献   

12.
p-PhOC6H4TeCl3 crystallises with a dimeric molecular unit. The two approximately square pyramidal coordination polyhedra are linked trans to each other through two bridging chlorine atoms. The dimeric units are further connected through Te…Cl secondary interactions producing a distorted octahedral geometry about each tellurium atom. The crystals are triclinic, space group P1, with unit cell dimensions a 8.521(2), b 10.917(2), c 14.813(2) Å, α 81.84(1), β 83.38(1), γ 88.41(1)°, V 1353.4(4) Å3 and Z = 2(dimers) from 3887 observed reflections [I > 3σ(I)], R = 0.0359.  相似文献   

13.
Treatment of 1,2-(E,E)-di(1-buta-1,3-dienyl)cyclohexanol (21) with potassium hydride in tetrahydrofuran at room temperature resulted in the facile formation of a 14-membered ring dienolate which on kinetic protonation provided cyclotetradeca-3,5,7-trien-1-one. This novel rearrangement which provides the basis for an efficient, eight unit ring expansion method was also observed when 5,8-dimethyl-5-hydroxy-1,3,7,9-decapentaene (28), the acyclic analogue of 21, was treated with potassium hydride in tetrahydrofuran. Methodology for the preparation of 21 and 28 including the preparation of 1-lithio-1,3-butadiene is also described.  相似文献   

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Some crystalline di- and tri-phenylstannyl esters [ArCS2SnPh3 and (ArCS2)2SnPh2] of aromatic dithio acids have been prepared in good yields and characterized. Preferential cleavage of the SnS bond of the ester was observed by treating them with primary and secondary amines as well as with phenacylidenetetramethylenesulfurane.  相似文献   

17.
The interaction of azobenzene and MnR(CO)5 (R  Me, Et, CH2Ph, CH2-C6Me5, COCF3, COCH2C6F5, COCH2OPh, Ph or C6F5) affords Mn(C6H4NNPh)-(CO)4, together with a binuclear complex Mn2(CO)6(C12H10N2) in some cases. The metallation reaction is shown to proceed most readily with Mn-(CH2Ph)(CO)5; with this reagent, the metallated complexes Mn(C6H4CH2PMe2)-(CO)3[PMe2(CH2Ph)] (two isomers) and Mn(C6H4CH2AsMe2(CO)4 have been obtained on treatment with EMe2(CH2Ph) (E  P and As, respectively).  相似文献   

18.
Homoharringtonine 2 and dehydrodesoxy homoharringtonine 4 were synthesized by partial esterification of cephalotaxine.  相似文献   

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Perfluoroalkylethylenes react with some carbon-, oxygen-, sulfur-, selenium-, nitrogen-, and phosphorus-based nucleophiles by formal SN2′ displacement of fluoride ion.  相似文献   

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