Magnesium Methyl radical

Acetophenone and magnesium methyl iodide yield 2-phenyl-l-propene. As can be seen from the equation, one at least of the radicals R, R1 Ru, must have a non-tertiary carbon linked in the intermediate compound to the hydroxy-magnesium-iodide carbon. 

The decomposition of methylcopper also proceeds via a radical mechanism and gives either methane or varying quantities of methane and ethane, according to the conditions of the decomposition. Costa et al. have found that the decomposition of pure dry methylcopper or of a suspension in heptane gave methane, via methyl radicals, and copper metal only (76, 78, 81). Methylcopper reagents containing magnesium... 

In order to resolve the issue of the possible adsorption of methyl radicals on the surface of the MgO-based catalysts Campbell and Lunsford conducted an MIESR experiment with an additional layer of magnesium oxide placed downstream from the Li/MgO catalyst It was expected that, if methyl radicals were adsorbed by the MgO surface, a significant decrease in the CH3 signal would have been observed. The results of this experiment conducted at 700 °C showed that tire presence of magnesium oxide increased production of methyl radicals, suggesting that no ads(Hption of methyl radicals occurs at this tonperature. Furthermore, it was concluded that no coupling of CH3 radicals takes place on the MgO catalyst... 

Table 1 ESR signal intensity normalized by the standard sample of magnesium oxide with Mn as impurities of the methyl radicals in the samples A-E and A -E and the ratio.

The reaction of an organic halide with a metal is an oxidation-reduction in which the metal is the reducing agent. As shown in the fohowing equahons for the reactions of methyl chloride with lithium and with magnesium, a single-electron transfer from the metal converts methyl chloride to a radical anion, which then dissociates to a methyl radical and chloride ion. Bond formahon between methyl radical and a metal species ( Li or Mg" ) follows. 

Acrylonitrile [271] polymers were prepared in bulk in high yields under controlled conditions at room temperature to 60°C in 30-90 min using radical catalysts with decomposition rate constants >1 hr Thus, 1600 g of acrylonitrile containing 300 ppm water was kept at 50 C, and 3.2 g of cumene hydroperoxide, 23.2 g of dimethyl sulfite, and 18.1 g of magnesium methylate in 150 cm of MeOH were added. The conversion achieved in 15 min represented a final conversion of 11% in a continuous polymerization system. 

Alkyl alkanoates are reduced only at very negative potentials so that preparative scale experiments at mercury or lead cathodes are not successful. Phenyl alkanoates afford 30-36% yields of the alkan-l-ol under acid conditions [148]. Preparative scale reduction of methyl alkanoates is best achieved at a magnesium cathode in tetrahydrofuran containing tm-butanol as proton donor. The reaction is carried out in an undivided cell with a sacrificial magnesium anode and affords the alkan-l-ol in good yields [151]. In the absence of a proton donor and in the presence of chlorotrimethylsilane, acyloin derivatives 30 arc formed in a process related to the acyloin condensation of esters using sodium in xylene [152], Radical-anions formed initially can be trapped by intramolecular addition to an alkene function in substrates such as 31 to give aiicyclic products [151]. 

The trimethylsilyl radical produced either rapidly dimerizes or reacts with solvent so that very clean ESR spectra of the radical anion, with minimum interactions with the counterion, can be obtained (116). Further reduction to dianions is very slow, and exhaustive reduction to anion radicals minimizes problems associated with exchange between anion radicals and unreduced substrate (115). It now appears that the solvent HMPA greatly facilitates the one-electron reduction, not only for trimethylsilylsodium, but also for organolithium and magnesium reagents (110). It was found that 0.1F solutions of methyl-, n-butyl-, or f-butyllithium or benzylmagnesium chloride will quantitatively reduce biphenyl to its radical anion in less than 10 minutes (110). 

The 4,7-dimethyl diquaternary salt of 4,7-phenanthroline is reduced in aqueous solution at a potential (E0) of —0.30 volt by a one-electron transfer to give a radical cation. The polarographic reduction of the salt has been studied in nonaqueous solvents.15,307 The electrochemical reduction of the salt has also been investigated.323 4,7-Phenanthroline 4,7-dimethiodide reacts with methyl magnesium iodide to give the expected 3,4,7,8-tetrahydro-3,4,7,8-tetramethyl-4,7-phenanthroline, which is unstable in air.284... 

Mixed aliphatic ethers containing methyl or ethyl radicals can be synthesized from the corresponding alkyl sulfate and magnesium alcoholates, e.g., methyl n-butyl, methyl cyclohexyl, and methyl isoamyl ethers (70-78%). A higher yield of ethyl isobutyl ether is obtained by substituting sodium for magnesium (70% vs. 30%). ... 

By itself, the formation of 97 takes on great significance. Its formation has never been observed in solution, only the products resulting from the reactions a, b and i, are observed Also the l-methyl-2,2-diphenylcyclopropyl radical does not dimerize to 97 even in a cage reaction but instead it follows the usual course of a tertiary o radical, it disproportionates. The only other time that dimerization of this radical has been observed was when the radical was formed on a magnesium metal surface . Thus, the reaction of the aggregates [(S)-(96)] resembles a surface reaction (see below). 

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