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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 ...
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, ...
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. ...
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 ...
Selective borane reductions of progesterone
(Elsevier, 1967)
A number of selective reductions using borane end metal borohydrides has been described. In our studies of hydroboration of steroid conjugated ketones under different conditions and with different solvents we have found ...
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 ...
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, ...
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 ...
Investigation of active carbon for fuel-cell electrodes
(Elsevier, 1969)
The influence of grain size, mode of catalyst impregnation, and different surface treatments on the electrochemical activity of active carbon for hydrogen fuel-cell electrodes was studied. The experiments were done in a ...
Studies on Chlorate Cell Process IV. Effect of Neutral Salts on Conversion of Available Chlorine to Chlorate
(IOP Publishing, 1969)
It has been shown that neutral salts, such as Nacl and and Naclo3 and their mixtures, cause an apparent increase in the thermodynamic dissociation constants of weak acids and bases. The pH value of aqueous salt solutions ...