59967-05-4Relevant articles and documents
Determining the Scope of the Organolanthanide-Catalyzed, Sequential Intramolecular Amination/Cyclization Reaction: Formation of Substituted Quinolizidines, Indolizidines, and Pyrrolizidines
Molander, Gary A.,Pack, Shawn K.
, p. 9214 - 9220 (2007/10/03)
The scope of the lanthanide-mediated, intramolecular amination/cyclization reaction was determined for the formation of substituted quinolizidines, indolizidines, and pyrrolizidines. A methyl group was installed at diverse positions in the substrates to d
Concerning the Mechanism of Grignard Reagent Formation. Evidence for Radical Escape and Return to the Surface of Magnesium
Ashby, E. C.,Oswald, John
, p. 6068 - 6076 (2007/10/02)
A study of the mechanism of formation of Grignard reagents using alkyl halide radical probes has been conducted.The effects of activation of the magnesium, temperature, concentration of the alkyl halide, magnesium to alkyl halide ratio, magnesium purity, the nature of the alkyl group, the nature of the halide group, and solvent (viscosity and basicity) on the formation of Grignard reagent were studied.The data obtained were used to test the earlier report by Garst that alkyl radicals, generated in the reaction of an alkyl halide with magnesium, diffuse freely into the solvent phase and return to the magnesium surface to form Grignard reagent.In this study cyclizable radical probes and radical traps were employed to study the extent to which radicals leave and return to the surface of magnesium to form Grignard reagent.In the particular system reported here, the data indicate that ca.25percent of the Grignard reagent is formed from radicals that diffuse into the solvent phase and than return to the magnesium surface to form Grignard reagent.
FREE RADICAL REARRANGEMENTS OF ORGANOCOBALOXIMES: ALKYNYL TO CYCLOALKYLIDENE AND HEXENYL TO CYCLOPENTYLMETHYL
Bougeard, Peter,Cooksey, Christopher J.,Johnson, Michael D.,Lewin, Melanie J.,Mitchell, Stewart,Owens, Paul A.
, p. 349 - 358 (2007/10/02)
Under irradiation by tungsten light in pyridine solution, several substituted alkylcobaloximes undergo rearrangement to more stable substituted alkyl- or alkenyl-cobaloximes.When the same reactions are carried out in the presence of carbon tetrachloride or chloroform, no rearranged organobaloximes are obtained, but a variety of organic products are obtained derived from the interception of transient organic radicals by the halogenated solvent.The rearrangements are rationalised in terms of a reversible homolysis of the carbon-cobalt bond, rearrangement of the organic radical and recapture by the cobalt(II) fragment to give complexes that are more stable to irradiation than their precursors.
