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Alkylation of carbonyl compounds in the TiCl4-promoted reaction of trimethylsilyl enol ethers with ethylene oxide
(Oxford : Pergamon-Elsevier Science Ltd, 2000)
Titanium tetrachloride promoted reaction of trimethylsilyl enol ethers with ethylene oxide affords homoaldol type products in moderate/good yields. The reaction is believed to proceed via the titanium enolates. (C) 2000 ...
Reactions with lead tetraacetate. I. Oxidation of saturated aliphatic alcohols. Part 1
(Elsevier, 1963)
It was recently shown that various steroid alcohols could react with lead tetraacetate in non-polar solvents to give tetrahydrofuran and tetrahydropyran derivatives. cyclization occurring when the position of and the ...
An improved preparation of 3-α-acetoxy-11,20-diketo-(5β)-pregnane, the key intermediate in the synthesis of 11-oxygenated corticosteroids
(Elsevier, 1967)
Although microbiological methods of introducing oxygen at C-11 of the steroid molecule are effective, it is obvious that purely synthetic way of producing cortisone and its analogs from bile acids or hecogenin have never ...
Transformation of steroidal 5α,8α-peroxides to the 14-membered ring containing 5,10;8,9-diseco-steroid derivatives
(Elsevier, 1985)
Thermal decomposition of steroidal 5α,8α-peroxides (such as 1) resulted in bisfragmentation of the C(5)-C(10) and C(8)-C(9) bonds, and elimination of acetic acid, to produce a new type of bicyclic compounds, namely ...
Annulations of isoquinoline and beta-carboline ring systems: synthesis of 8-oxoprotoberberine derivatives
(Oxford : Pergamon-Elsevier Science Ltd, 2011)
Annulation processes of isoquinoline and p-carboline compounds have been investigated leading to synthetic routes for the preparation of 8-oxoprotoberberine derivatives. The key steps combined a diene formation/Diels-Alder ...
Magnetic criteria of aromaticity in a benzene cation and anion: how does the Jahn-Teller effect influence the aromaticity?
(Oxford : Pergamon-Elsevier Science Ltd, 2012)
The aromatic/antiaromatic behavior of the Jahn-Teller UT) active benzene cation and anion has been investigated using Density Functional Theory (DFT) calculations of Nuclear Independent Chemical Shifts (NICS) and magnetic ...
Titanium tetrachloride promoted reaction of silyl ketene acetals with epoxides: a new method for the synthesis of gamma-butanolides
(Oxford : Pergamon-Elsevier Science Ltd, 2002)
A new method for the synthesis of gamma-butanolides is described. The titanium tetrachloride promoted reaction of silyl ketene acetals with epoxides, followed by acidic work-up, affords the corresponding butyrolactones in ...
A highly regioselective, protecting group controlled, synthesis of bicyclic compounds via Pd-catalysed intramolecular cyclisations
(Oxford : Pergamon-Elsevier Science Ltd, 2013)
Intramolecular Pd-catalysed cyclisation reactions for the preparation of bicyclic compounds have been studied as a model system towards the synthesis of corialstonine and corialstonidine. Significant differences in reactivity ...
Study of the intramolecular Heck reaction: synthesis of the bicyclic core of corialstonidine
(Oxford : Pergamon-Elsevier Science Ltd, 2015)
The intramolecular Heck reaction has been examined for the preparation of the core bicyclic structure of corialstonidine. Initial attempts to cyclise a vinyl iodide moiety onto a cyclic allyl alcohol were complicated by ...
Linear free energy relationships of half-wave reduction potentials of (E)-4-aryl-4-oxo-2-butenoic acids
(Elsevier, 2010)
Half-wave reduction potentials of a set of twelve (E)-4-aryl-4-oxo-2-butenoic acids obtained by direct current polarography in methanol are reported. E1/2 is correlated with Hammett sigma values as well as with values of ...