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Opening of steroid ring a by means of lead tetraacetate
(Elsevier, 1964)
The lead tetraacetate oxidation of cholestan-1β-ol and cholestan-1α-ol in benzene solution did not afford cyclic ethers but resulted, in major part, in the opening of ring A with formation of 1,10-seco-aldehydes. In addition, ...
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 ...
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, ...
Reactions with lead tetraacetate-IV. Oxidation of saturated aliphatic alcohols-II; Alcohols of low molecular weight
(Elsevier, 1965)
The action of lead tetraacetate on ethanol, 1-propanol, 2-propanol and 2-butanol has been studied under various experimental conditions, and it was found that the tetravalent lead compound reacts with alcohols in ways not ...
Lead tetraacetate oxidation of saturated aliphatic alcohols.-III. Unbranched primary and secondary alcohols
(Elsevier, 1965)
The action of lead tetraacetate, in benzene solution, on various unbranched primary and secondary aliphatic alcohols containing 4 to 12 carbon atoms has been investigated and the ratio of carbonyl compounds, cyclic ethers ...
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 ...
The conformational equilibrium of 1,3-dichloro-5-methylcyclohexane
(Elsevier, 1981)
Two of the stereoisomers of the title compound were prepared and their dipole moments were measured. For the r-1,c-3-dichloro-t-5-methylcyclohexane, the free energy difference between conformers with axial-axial (aa) and ...
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 ...
Configuration and reactivity of ten-membered 5,10-seco-compounds obtained by fragmentation of 5-hydroxy-steroids
(Elsevier, 1966)
Assignment of configuration to the 1,10-double bond in the cis-trans isomeric 3β-acetoxy-5,10-seco-1,10-cholesten-5-ones has been achieved by means of NMR spectrometry. Some reactions of these new compounds have been studied ...
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. ...