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1.
2-Vinylindoles are obtained from the Fischer indolization of α,β-unsaturated ketones. Heating 2-(2-methylpropenyl)indole (4) with the Vilsmeier reagent (DMF/POCl3) gave 2-methylcarbazole in good yield, presumably via an electrocyclic ring closure of a hexatrienic intermediate.  相似文献   

2.
N-Acylaziridines couple efficiently with organolithium and Grignard reagents to produce ketones in high yields.  相似文献   

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All four isomers of substituted 3-alkylthio-4-hydroxybutenes have been synthesised: both the geometry of the double bond and the relative stereochemistry of the two chiral centres are controlled.  相似文献   

5.
General methods for inverting the stereochemisty of vinyl tertiary-alcohols such as 2 and 5 into 3 and 8 respectively are described. The procedures employ a [2,3] sulfoxide rearrangement and will facilitate the extended use of the oxy-Cope rearrangement to a variety of related ring systems.  相似文献   

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Treatment of halo-F-methylphosphonium salts with potassium fluoride and halogen (I2, Br2, ICl, IBr) gives modest yields of halo-F-methanes. This method of preparation augments the classical Hunsdiecker approach to these materials.  相似文献   

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Starting from the coupling reaction of alkyl cuprates with 1-alkynyl-2-propenyl acetates, the title compounds were prepared by short convenient syntheses.  相似文献   

10.
The facile decomposition of methyl chlorodifluoroacetate, induced by either lithium chloride/hexamethylphosphoric triamide complex or potassium fluoride/18-Crown-6 complex, has been carried out in the presence of a variety of olefinic substrates to yield the corresponding gem-difluorocyclopropanes. The ester decomposition has been determined to yield “free” difluorocarbene via a three-step process involving an intermediate chlorodifluoromethide ion.  相似文献   

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Flow vacuum thermolysis (500–650°) of 1,2-cyclonona- and 1,2-cyclodecadienes yields, as primary products, terminal enynes and enedienes. Secondary intramolecular Diels-Alder reactions of the enedienes afford cis and trans bicyclics.  相似文献   

16.
The C4erythro and threo diols (7) and (8) are converted either into the chiral epoxides (13) and (15) or into the enantiomers (14) and (16); the epoxide (13) is used as chiral synthon for the preparation of (3S,4S) 4-methyl-3-heptanol (21).  相似文献   

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N-Acyl derivatives of D,L-acosamine and D,L-ristosamine were synthesized with high stereo selectivity utilizing intramolecular Michael addition of γ- and δ-carbomoyloxy-α,β-unsaturated esters.  相似文献   

19.
Base catalyzed decompositions of 2-(α-ethoxycarbonyl-benzyl)-3-phenyl-oxaziridines carried out in benzene in an atmosphere of oxygen yielded N-benzoyl benzamides along with ethyl phenylglyoxylate imine and benzaldehydes.  相似文献   

20.
J Leitich 《Tetrahedron letters》1980,21(32):3025-3028
The relative rates of formation of cis and trans [2+2]cycloadducts of benzyne to cis, trans- and cis, cis-1,5-cyclooctadiene, trans- and cis-cyclooctene are discussed and properties of the adducts (e.g., their unusual hydrogenation) are described.  相似文献   

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