38334-98-4Relevant articles and documents
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Maeda,Y.,Ingold,K.U.
, p. 4975 - 4981 (1979)
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Palladium-Catalyzed Alkoxycarbonylation of Unactivated Secondary Alkyl Bromides at Low Pressure
Sargent, Brendon T.,Alexanian, Erik J.
, p. 7520 - 7523 (2016/07/06)
Catalytic carbonylations of organohalides are important C-C bond formations in chemical synthesis. Carbonylations of unactivated alkyl halides remain a challenge and currently require the use of alkyl iodides under harsh conditions and high pressures of CO. Herein we report a palladium-catalyzed alkoxycarbonylation of secondary alkyl bromides that proceeds at low pressure (2 atm CO) under mild conditions. Preliminary mechanistic studies are consistent with a hybrid organometallic-radical process. These reactions efficiently deliver esters from unactivated alkyl bromides across a diverse range of substrates and represent the first catalytic carbonylations of alkyl bromides with carbon monoxide.
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.