The first contribution t o the alkaline autoxidation of ketones was by Doering and Haines who, using t-butyl alcohol and potassium tbutoxide as solvent and base, respectively, obtained acids and aldehydes as the products. Scheme 1 was postulated t o account for the results:
With an Appendix on the Spectroscopic Determination of the Structure of the Reaction Products. By C. LA LAU.)Several types of alkylperoxy-radicals (RO*O*) were prepared both by cobalt-catalysed decompositions of the corresponding hydroperoxides (RO-OH) and by addition of alkyl radicals (R-) to oxygen. Their reactions with a number of 2 : 4 : 6-trialkylphenols (AH) have been investigated. The main products appeared to be peroxides (RO*Oh) having the structure of alkylperoxy-2 : 4 : 6-trialkylcyclohexadienones. If a P-methyl group was present in the phenol, stilbenequinones were also formed. The results are discussed in relation to the inhibitory activity of phenols in autoxidation.FOR most liquid-phase autoxidations of hydrocarbons the propagation sequence generally accepted is :Termination may occur by interaction of the chain-carrying radicals (Re and RO.0.) or by reaction with an inhibitor (Bolland, Quart. Reviews, 1949, 3, 1). The amounts of inhibitor required to suppress oxygen absorption are generally very small-often as little as 0-01%-probably as a result of the large overall kinetic chain lengths. In consequence, the amounts of products formed from the inhibitor are too small for a detailed study, which seriously handicaps investigations into the mode of action of antioxidants.Abundant evidence is available (Bolland, loc. cit.) as regards the predominating part played by alkylperoxy-radicals (RO-0.) in autoxidation. Since the concentration of alkyl radicals (Re) is generally low as a result of their rapid reaction with oxygen to form alkylperoxy-radicals, it seems plausible to assume the inhibitor to operate mainly by reactions with RO-0.. In order to investigate the latter reactions by isolation of products, methods are required for the preparation of alkylperoxy-radicals on a sufficient scale while avoiding the simultaneous oxidation of an excess of other products. Recent literature has dealt to some extent with methods of this kind. Cosgrove and Waters (J., 1951, 388)
There are considerable structural deficits in outpatient treatment facilities involved in management of patients suffering from chronic headache, chronic back pain and cancer pain. Realisation of standards according to the "Schmerztherapievereinbarung" needs organisation of an interdisciplinary network between the different specialties necessary for pain management. Interdisciplinary cooperation should be supported by the official organization of the medical self-government in Germany--the Kassenärztliche Vereinigung--which has to assure optimal conditions for outpatient treatments.
Badhztisweg 3) IN a previous communication1 we reported on substitution a t alkane-hydrogen by a proton, the reactions (1) and (2) in hydrogen fluoride solution :driving force being the formation of the &able(1) tertiary butyl cation.We have now found that with neopentane n (2) reaction of type (+-which would lead to the primary neopentyl cation-does not occur, but Me,C+SbF,-+ H, Me,CH + H*SbF,-Reaction (2) may be described as an electrophilic
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