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Toyonari ItoTakahiro Tokuyasu Araki MasuyamaMasatomo Nojima Kevin J McCullough 《Tetrahedron》2003,59(4):525-536
Bis(sym-collidine)iodine (I) hexafluorophosphate-mediated cyclization of unsaturated hydroperoxides, prepared by a variety of different methods, afforded the corresponding 10- to 20-membered macrocyclic peroxides having two or three peroxide units located within one ring in moderate yields. By analogy, cyclization of unsaturated alcohols having one or two peroxide bond in the chain afforded the corresponding cyclic ethers. The efficiency of the latter reactions were found to be a function of the structure of the alcohols. 相似文献
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This paper reports results obtained in a study on the palladium-catalyzed hydrostannation of substituted propargyl alcohols with the bulky trineophyltin hydride (1). The reaction of 1 with 10 propargyl alcohols containing one up to three substituents, was carried out in THF at room temperature leading to the corresponding allylstannanes following in all cases a syn addition stereochemistry. These additions took place in good to excellent yields and, mostly, with a high degree of stereoselectivity. The results obtained suggest that the observed α/β regioselectivity might be ascribed to the steric bulk of the proximal substituents rather than to electronic effects. Full 1H-, 13C-, and 119Sn NMR characteristics are included. 相似文献
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β-Amino alcohols possessing an E vinylsilane moiety were cyclized in the presence of N-bromosuccinimide to afford diastereoisomerically pure polyfunctional azetidines. These azetidines were then transformed into enantiopure β-amino alcohols with a Z vinylic bromide moiety. 相似文献
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Hui-Lan Yue 《合成通讯》2013,43(4):600-610
Indium-promoted allylation of alkynes by direct use of allyl alcohols as the allylating agents has been developed under mild conditions, in which a wide range of allylic alcohols and alkynes (both aromatic and aliphatic alkynes) could be tolerated, and the corresponding halogen-substituted 1,4-dienes were obtained in moderate to excellent yields. 相似文献
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An aprotic imidazole based zwitterionic-salt, 4-(3-methylimidazolium)-butane sulfonate has been found to be an efficient organocatalyst for tetrahydropyranylation by the reaction of 3,4-dihydro-2H-pyran (DHP) and different aliphatic alcohols as well as various phenolic compounds. The notable advantages of the present method are general applicability to various alcohols, clean reaction, production of no hazardous waste, open air reaction conditions and high yields. The catalyst can be reused without the loss of significant catalytic activity. 相似文献
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Lukas Werner 《Tetrahedron》2010,66(21):3761-3928
Conjugated dienes were converted to 1,2-oxazines by reaction with an acyl nitroso dienophile. The oxazines were reduced to 1,4-N-acetylamino alcohols, which were rearranged to the corresponding oxazolines upon treatment with methanesulfonyl chloride or anhydride. The oxazolines yielded 1,2-N-acetylamino alcohols upon hydrolysis. Thus either 1,4- or 1,2-N-acetylamino alcohols are available from 1,3-dienes via this methodology. Experimental and spectral data are provided for all new compounds. 相似文献
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David M. Hodgson Christopher R. Maxwell Edyta Paruch Ian R. Matthews 《Tetrahedron》2004,60(16):3611-3624
The use of (−)-sparteine as an external chiral ligand in enantioselective organolithium-induced alkylative double ring-opening of dihydropyrrole epoxides and 7-azanorbornene-type epoxides gives unsaturated acyclic amino alcohols, and amino cyclohexenols in up to 87% ee. 相似文献
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The utility of acetylenic aldehydes in Baylis-Hillman reactions giving allyl propargyl alcohols in moderate to good yields is reported. 相似文献
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A one pot synthesis of α-trifluoromethyl unsaturated acids via a [3,3]-sigmatropic rearrangement of allyl (or propargyl) fluorovinyl ethers is described. By proto- and iodolactonization, these acids lead to the corresponding trifluoromethylated lactones. 相似文献
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This paper presents the experimentally determined retention indices (RI(TMS)) for a set of 75 silylated terpenols (33 monoterpenols and 42 sesquiterpenols). The attempt was made to assess the dependence of RI(TMS) on RI (for non-silylated terpenols) and on RI(Ac) (for acetylated terpenols). Satisfactory linear regression parameters (RI(TMS)=b(0)+b(1)RI) were observed for tertiary substituted monoterpenols and primary or secondary substituted sesquiterpenols. The mass spectra of silylated terpenols that were not found in the available literature are in Supplementary information. 相似文献
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The isomerisation of α-acetylenic alcohols to ethylenic carbonyl derivatives and the isomerisation of α-ethylenic alcohols to the corresponding allyl alcohols may be effected in good yields in a single step using oxometallic derivatives. The vanadate esters are particularly efficient. Mechanistic explanations are given. 相似文献
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《Tetrahedron letters》1986,27(20):2211-2214
The reaction of aryl- and vinylpalladium compounds with vinylic and allylic epoxides provides an excellent, high yielding, regio- and stereoselective route to functionally substituted allylic alcohols which can be made catalytic in palladium. 相似文献
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Fabio Ragaini Tatiana Longo Sergio Cenini 《Journal of molecular catalysis. A, Chemical》1996,110(3):L171-L175
Several different palladium-based catalytic systems have been investigated for the addition of urethane (NH2COOEt) to olefins. A catalytic system based on PdCl2(CH3CN)2/CuCl/O2 gave good results only in the case of the activated olefin methyl acrylate. Catalytic systems of the type Pd(acac)2/phosphorus ligand/acid. previously used to catalyse the telomerisation of conjugated olefins with amines, gave the desired adduct. together with the product of addition of one molecule of urethane and two molecules of diolefin, in the case of isoprene and 2.3-dimethylbutadiene. The main by-products were the dimers of the diolefin, whereas the selectivity in urethane appears to be high. In no case could the addition of urethane to an unactivated non-conjugated olefin be achieved. 相似文献
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Phosphatidylinositol polyphosphate (PIPx) are related with tyrosine kinase activation and cell proliferation and carcinogenesis. PIPx is an important target compound for synthetic organic chemist. PIPx having saturated fatty acid components have been reported. Recently we have succeeded in the synthesis of phosphatydylinositol-3,4,5-trisphosphate with unsaturated fatty acid component by the reaction of diethyl chlorophosphite with l,2-di-O-cyclohexylidene-3,4-O-(tetraisopropyldisiloxane 1,3-diyl)-6-O-(4-oxopentanoyl)-myo-inositol. 相似文献
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J.S. Yadav B.V. Subba Reddy T. Srinivasa Rao K.V. Raghavendra Rao 《Tetrahedron letters》2008,49(4):614-618
Propargylic alcohols undergo smooth deoxygenative allylation with allylsilanes in the presence of a solution of 10 mol % of copper(II) tetrafluoroborate in acetonitrile to afford the corresponding 1,5-enynes in good to high yields under mild and neutral conditions. Scandium triflate is also found to catalyze efficiently the nucleophilic substitution of propargylic alcohols with allylsilanes. 相似文献
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M. A. Pudovik G. M. Saakyan V. K. Khairullin N. A. Khailova A. N. Pudovik 《Russian Chemical Bulletin》1999,48(4):806-807
Addition of alcohols to bis(chloromethyl)phosphinoyl isocyanate, as well as the reaction of bis(chloromethyl)phosphinoyl chloride
with urethanes or their silylated derivatives, gave the corresponding phosphorylated carbamates which undergo cyclization
into 1,3,4-oxazaphospholines under the action of Et3N.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 810–811, April, 1999. 相似文献