Methyl iodide reagent

Methyl desoxyglycyrrhetate 61 Methyidigoxin 104 Methyl glycyrrhetate 61 Methyl iodide reagent 70 N-Methylphenylalanine 89 Methylsuccinic acid 249 Methyl sugars 188... 

Dimethyl sulfoxide (DMSO), reagent grade Methyl iodide, reagent grade Silica gel (Merck)... 

Barbier reported (1) in 1899 that a mixture of methyl iodide, a methyl ketone, and magnesium metal in diethyl ether produced a tertiary alcohol. Detailed studies by his student Victor Grignard are documented in his now classical doctoral thesis, presented in 1901. Grignard estabUshed (2) that the reaction observed by Barbier could be separated into three distinct steps Grignard reagent formation, Grignard reaction, and hydrolysis. 

Pyrroles do not react with alkyl halides in a simple fashion polyalkylated products are obtained from reaction with methyl iodide at elevated temperatures and also from the more reactive allyl and benzyl halides under milder conditions in the presence of weak bases. Alkylation of pyrrole Grignard reagents gives mainly 2-alkylated pyrroles whereas N-alkylated pyrroles are obtained by alkylation of pyrrole alkali-metal salts in ionizing solvents. 

The leaving group in the alkylating reagent has a major effect on whether C- or O-alkylation occurs. In the case of the lithium enolate of acetophenone, for example, C-alkylation is predominant with methyl iodide, but C- and O-alkylation occur to approximately equal extents with dimethyl sulfate. The C- versus O-alkylation ratio has also been studied for the potassium salt of ethyl acetoacetate as a function of both solvent and leaving group. ... 

Isotope labeling by derivative formation with deuterated reagents is useful for the preparation of analogs such as dg-acetonides, da-acetates, da-methyl ethers, dg-methyl esters, etc. The required reagents are either commercially available or can be easily prepared. (The preparation of da-methyl iodide is described in section IX-F. Various procedures are reported in the literature for the preparation of dg-acetone, da-diazometh-ane57.i63.i73 and da-acetyl chloride. ) These reactions can be carried out under the usual conditions and they need no further discussion. A convenient procedure has been reported for the da-methylation of sterically hindered or hydrogen bonded phenolic hydroxyl functions by using da-methyl iodide and sodium hydroxide in dimethyl sulfoxide solution. This procedure should be equally applicable to the preparation of estradiol da-methyl ether derivatives. 

Enamines are stable to Grignard reagents, methyl iodide and lithium aluminum hydride. 

Polymer-bound phenyliodine difluoride, which also has been used as a reagent to add fluorine to alkenes, can be prepared by the addition of xenon difluoride to the polymer [134, 135 136] Methyl iodide is converted to trifluoro methyliodine difluoride by treatment with fluorine at -110 C [137] Perfluoro-alkyliodine tetrafluorides could be synthesized from the perfluoroalkyliodine difluorides and fluorine [138] or chlorine trifluoride [139] Perfluoroalkyl [140] and perfluoroaryl [141] iodides are oxidized to the corresponding iodine difluorides by chlorine trifluoride. 

Hoshino and his co-workers reported that treatment of the Grignard reagent obtained from tryptamine (23), by the action of a suitable alkyl magnesium halide, with methyl iodide in benzene did not give the expected indolonino derivative 24 instead dinordeoxyeseroline (25) was obtained. 

Sebastian also observed that although alkylation of the indole Grignard reagent with methyl iodide in tetrahydrofuran at 23° gave essentially 3-methylindolc, variable amounts of 1- and 3-methyl-indole were obtained on alkylation of the alkali metal salts of indole under similar conditions. Sebastian s results were qualitatively similar to those obtained earlier by Lerner and more recently by Cardillo who studied the reaction of a number of organometalhc... 

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