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J. Barrau H. Lavayssiere G. Dousse C. Couret J. Satgé 《Journal of organometallic chemistry》1981,221(3):271-277
Desulfuration reactions of germadithiolanes by trialkylphosphines lead to germathiones via intermediate germathietanes. The formation of germylenes finally observed arises from reduction of germathiones by trialkylphosphines. Analogous reduction reactions of germanones by three coordinated linear and cyclic phosphorus compounds are also described. 相似文献
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《Tetrahedron》1988,44(10):2903-2912
The reactionz of organomagnesium compounds with cyclic lactols and the phthalde show a high chemioselectivity and provide respectively corresponding monoalkylated cyclic lactones and diols We also observe that the formation of bridged tricyclic lactones stereoselectively yields to thetransisomer. In the same way, we describe an easy and general method for the synthesis of diols, precursors of dibromides and cyclic ethers. 相似文献
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Hydroboration of carbon—carbon double bonds of polyalkadienes leads to macromolecular organoboranes which can engage in organic reactions described by H. C. Brown. We have particularly considered the reactions of organoboranes with α-carbonylethylenic compounds which can occur with high yields by using bis-boracyclanes as hydroborating agents. The aim of our paper is to show, using model molecules and low polymers, the ability of bis-borinane, of bis-(dimethyl-3,5 borinane) and of bis (dimethyl-3,6 borepane) to react totally with unsaturated groups of polyalkadienes. For this purpose, we have used the possibilities given by oxidation of the alkylboranes giving alcohols or polyols easier to characterize than alkylboranes themselves. 相似文献
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Treatment of 3-cyano 1,3-dichloropyrrolidine-2,5-diones with two equivalents of a phosphine, PY3, affords an ion pair, then a salt consisting of a dianion and two halophosphonium cations. This salt gives Cl2PY3 and a phosphobetaïne 6 which carries a P-O bond. Rearrangement of the phosphobetaïne 6, Y=Ph or p-MeC6H4, catalysed by halide ions, gives a ne? phosphobetaine 7 which is carrying a P-N bond. 相似文献
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The reaction of 1,4,6,9-tetraoxa-5-phospha(V)spiro[4,4]nonane 1 with ethyl vinyl ether gives a spirophosphorane containing a PC bond, 5-(β-ethosyethyl)-1,4,6,9-tetra-oxa-5-phospha(V) spiro[4,4]nonane 2 (radical reaction), and a tricoordinated phosphorus compound, 2-(3,5-di-oxa-4-methylheptanoxyl)-1,3,2-dioxaphospholane 3 (ionic reaction). 2,2,3,3,7,7,9-Heptamethyl-1,4,6-trioxa-9-aza-5-phospha(V) spiro[4,4]nonane 6 gives exclusively a spirophosphorane containing a PC bond, 5(β-ethoxyethyl)-2,2,3,3,7,7,9-heptamethyl-1,4,6-trioxa-9-aza-5-phospha(V)spiro[4,4]nonane 7. The reaction of 1 with alcohol or ethyleneglycol and enamine yields a pentaoxyspirophosphorane and an amine by an oxidation-reduction condensation. Suggested mechanisms of these reactions are presented. 相似文献
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The substituents F, Cl, Br, CN, NO2, COOR, CONR2, P(O)R2 do not interfere with the reaction of MoF6 with aromatic aldehydes and ketones yielding gem-difluoro compounds, but OH, NH, OR, NR2, CC, react preferentially with MoF6 and prevent the reaction at CO. Yields of gem-difluoro compounds are enhanced with electron-attracting substituents on the carbonyl derivative, and are lowered when the CO group is sterically hindered. The hydrolytic stability of the RCF2R′ compounds vary widely with the nature of R and R′. Some reactions on R and R′ leave the CF2 group unaffected. Thus a number of new CF2 compounds are prepared including α,α-difluoroalkyl substituted benzyl alcohol32 benzylamines34, 36 benzaldehyde27, benzoic acids24, 28, 31, 35.1H and19F NMR data are given for all the new derivatives. The mechanism of the conversion is tentatively postulated. 相似文献
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High stereoselectivity was observed in the reactions of secondary alkylmagnesium compounds with bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride and lactone 2 leading respectively to the formation of diastereomeric lactones and primary-secondary diols. 相似文献
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This work deals with the reactions of metal carbonyl-halide adducts with Lewis acids [M(X → Lewis acid)(CO)aLb (L = PR3, π-Cp)]. Results are given regarding electric conductivity measurements in solution and IR spectra, as well as the preparation and study of a new class of metal nitrosyl-halide adducts, [M(X → Lewis acid)(NO)aLb]. A classification of Lewis acids is attempted following their electron-acceptor properties. 相似文献
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The reactions of spirophosphoranes containing a PH bond with aldehydes, imines, and animals lead to spirophosphoranes (10–10) containing a PC bond, while with acid chlorides, β-functional phosphiates are formed (compounds 35–38). Dependeing on the nature of the heteroatom attached to phosphorus, the reaction of spirophosphoranes with phenyl isocyanate gives a spirophosphorane (YHOH, compounds 31 and 32) or a phosphite (YHNHR, compounds 33 and 34). 相似文献
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In order to evaluate the crystal effect on the molecular geometry of substituted derivatives of benzenechromium tricarbonyl, favoured conformations of several complexes (substituted at the arene ring or the metallic moiety) in the gaseous state have been determined by the EHT method and compared to the solid state conformations. In most cases the two conformations are similar. 相似文献
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Cycoladducts of furfurylakyl and arylketones with methyl acetylendicarboxylate undergo acid-catalysed rearrangement in high yield to 6-hydroxyphthalates bearing an acetonly or a phenacyl group in the 3-positionl. These phthalic compounds are useful intermediates for the synthesis of polyfunctional derivatives in the isocoumarin and the isoquinoline series. 相似文献
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This study is devoted to two typical systems: solid fluoride (CsF), UF6 and volatile fluoride (NOF), UF6. The differences in the dissociation pressures of CsUF7 and Cs2UF8 and of NOUF7 and (NO)2UF8 along with spectral observations make it possible to prepare these compounds in a pure form. Vibrational spectroscopic studies and 19F chemical shift measurements allow one to propose symmetries corresponding to point group D5h and Oh for the heptafluoroanions and the octafluoroanions respectively. Crystal forces are likely responsible for the observed slight lowering in symmetry form the above idealized structure. At low temperature, a change of structure is observed for NOUF7, the symmetry for the heptafluoroanion becoming lower or equal to the symmetry corresponding to the C2v. group. 相似文献
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《Journal of organometallic chemistry》1977,133(2):169-176
Reactivity of organotinamines of pyrazole, imidazole, 1,2,4-triazole and benzotriazole towards alkyl halides has been studied. Primary halides give the corresponding N-alkylated heterocycles in quantitative yield. Reactivity decreases with secondary and tertiary halides. A mechanism is proposed for these reactions. 相似文献