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The reaction of lead tetra-acetate with some unbranched α,ω-diols
(Elsevier, 1969)
Unbranched α,ω-diols are mainly converted by means of lead tetra-acetate in refluxing benzene to the corresponding ethers of di-α-tetrahydrofuryl, di-α-tetrahydropyryl and/or α-tetrahydrofuryl-α′-tetrahydropyryl type. Thus, ...
Studies of the regioselective ring-opening closing mode of functionally different thiazolidine type enaminones: en route to the synthesis of trithiaazapentalene derivatives
(Oxford : Pergamon-Elsevier Science Ltd, 2013)
Trithiaazapentalene derivatives were prepared by the reaction of 2-alkylidene-4-oxothiazolidines with Lawesson's reagent. They are classified as two structurally different trithiaazapentalene compounds that have different ...
A novel pimara-8(9),15-diene from lycopus europaeus
(Pergamon Press, 1985)
Identification of a novel trioxygenated Δ8(9),15_ pimaric acid methyl ester from plant species Lycopus europaeus by means of two-dimensional 1H NMR spectroscopy (COSY and NOESY) is reported. © 1985.
Lead tetraacetate oxidation of saturated aliphatic alcohols-IV. The formation of six-membered cyclic ethers
(Elsevier, 1965)
The lead tetraacetate oxidation of saturated aliphatic alcohols, with structures which do not permit 1,5-cyclization, gave tetrahydropyran derivatives in yields not exceeding 16%. The formation of a small amount of the ...
Intramolecular cyclization of 3β-acetoxy-16-picolinylidene-5-androsten-17-one by catalytic hydrogenation
(Elsevier, 1970)
Intramolecular cyclization by catalytic hydrogenation of 3β-acetoxy-16-picolinylidene-5-androsten-17-one (IV) (80° and 50-60 atm of hydrogen pressure over Pd/C as catalyst) gives rise to the formation of two cyclic products, ...
Criteria for the determination of the stereochemistry of steroidal indolizidines
(Elsevier, 1974)
E/F-Indolizidine steroids, which represent a structural unit of Solanum alkaloids, have been synthesized and used to evaluate criteria (IR—Bohlmann bands,1a-c —hydrogenbond,2a-e NMR,3a-c mass spectra,4 kinetic studies of ...
Alkylation of carbonyl compounds in the TiCl4-promoted reaction of trimethylsilyl enol ethers with epoxides
(Oxford : Pergamon-Elsevier Science Ltd, 2001)
Titanium tetrachloride promoted reaction of trimethylsilyl enol ethers with ethylene oxide affords homoaldol type products in moderate/good yields. Monosubstituted epoxides react regioselectively: the nucleophilic attack ...
Lead tetra-acetate oxidation of saturated aliphatic alcohols-V. Factors influencing the formation of cyclic ethers and carbonyl compounds
(Elsevier, 1966)
Factors influencing the relative rates of the homolytic and heterolytic processes in the lead tetra-acetate oxidation of unbranched primary and secondary aliphatic alcohols have been investigated, with a view to determine ...
Acid-catalyzed rearrangement of some steroidal isoxazolidines
(Elsevier, 1999)
Acid-catalyzed reaction of the steroidal Δ 1 -unsaturated 3β,5β- epoxyimino compound 2 and Δ 3 -unsaturated 1β,5β-epoxyimino products 3 and 7, results in intramolecular rearrangement involving the N-CH 3 group to give the ...
The reaction of lead tetra-acetate with some acyclic hydroxy-ethers
(Elsevier, 1966)
By means of lead tetra-acetate in refluxing benzene open-chain 1,2-, 1,3-, 1,4- and 1,5-hydroxy-ethers are mainly converted to the corresponding five-membered or six-membered cylic products. Thus, 2-alkoxy-1-ethanols afford ...