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Catalytic oxidations of enolizable ketones using 2-alkylidene-4- oxothiazolidine vinyl bromide
(Oxford : Pergamon-Elsevier Science Ltd, 2011)
Direct oxidation of enolizable ketones to α-hydroxy derivatives, vicinal dicarbonyls or tricarbonyl compounds has been achieved by a catalytic amount of 2-alkylidene-4-oxothiazolidine vinyl bromide in DMSO as a solvent. ...
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 ...
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 ...
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 ...
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 ...
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, ...
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.
Reactions with lead tetraacetate-I. Oxidation of saturated aliphatic alcohols part 1
(Elsevier, 1964)
When oxidized with lead tetraacetate 1-heptanol and 1-octanol undergo cyclization to give as major products the corresponding 2-alkyltetrahydrofurans, accompanied by a small amount of the isomeric tetrahydropyran derivatives. ...
Corrigendum to: Organocatalyzed Tsuji-Trost reaction: a new method for the closure of five- and six-membered rings (vol 65, pg 10485, 2009)
(Oxford : Pergamon-Elsevier Science Ltd, 2010)
Regioselective synthesis of 1,3-thiazines by sequential 4-oxothiazolidine to 1,2-dithiole to 1,3-thiazine transformations: role of intramolecular non-bonded S/O interactions
(Elsevier, 2007)
A new synthetic approach to 2,3-dihydro-4H-1,3-thiazine derivatives based upon reductive rearrangement of 1,2-dithiole-3-ylidene thiones has been developed. In turn, the 1,2-dithiole derivatives were prepared by an efficient ...