Isolation of quasiphosphonium intermediates.

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  • English
ContributionsPolytechnic of North London. Department of Chemistry.
ID Numbers
Open LibraryOL14803250M


Part 3. Preparation, structure, and reactivity of alkoxyphosphonium halides in the reactions of Isolation of quasiphosphonium intermediates. book diphenylphosphinite, dineopentyl phenylphosphonite, and trineopentyl phosphite with halogenomethanes and the effect of phenoxy-substituents on the mechanism of alkyl–oxygen fission in Michaelis–Arbuzov reactions.

Quasiphosphonium intermediates—IV 1: Isolation and identification of intermediates in the arbuzov and perkow reactions of neopentyl esters of phosphorus(III) acids with α-halogenoacetophenones Imre Petneházy, Gyöngyi Szakál, László Tõke, Harry R Hudson.

The reaction of dialkyl aroylphosphonates with trialkyl phosphites leads to the formation of novel quasi-phosphonium ylides which in some cases thermally rearrange to the bisphosphonates.

2-Substituted dialkyl aroylphosphonates may also undergo intramolecular cyclisation under these conditions. Evidence is. 1. On the basis of the behavior of perfluoroisobutene and perfluorocyclobutene, it was shown that the previously described reaction of perfluoro olefins with triethyl phosphite takes place in two stages; as a result of the first stage a triethoxyfluoro (perfluoroalkenyl) phosphorane is obtained, and under more severe conditions, this decomposes with formation of the final Arbuzov rearrangement Cited by: 1.

Quasiphosphonium intermediates [R 1 R 2 P + (OR 3)R 4]X – were isolated and completely characterized in cases where the step (b) is difficult to proceed due to the nature of the R 3 group as for aryloxy (R 3 = aryl) and sterically hindered alkoxy derivatives (R 3 = neopentyl, trityl, and bicyclo[]heptyl) or the low nucleophilicity of.

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The hydrolysis of quasiphosphonium salts 8a and 8b involving two hydroxyphosphorane intermediates 10a and 10b. Scheme 7. The intramolecular transesterification of the 2-hydroxyphenyl phosphite Reactive intermediates occur only in one of the intermediate steps but in the case of other chemical reactions, they take more than one elementary steps.

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