Methyl arylacetates

Selective monoalkylation of methyl aryl-acetates by alkylhalides is difficult with conventional bases. It may be achieved by application of the three-step procedure outlined above adding (33) to the methyl arylacetates at a low temperature... 

A new perspective for safe and highly selective mono-N-and mono-C-alkylations Selective Mono-Methylation of Arylacetoni-triles and Methyl Arylacetates by Dimethylcarbonate... 

Methyl arylacetates.2 Aryl methyl ketones are converted into methyl arylacetates by reaction with BF3 etherate and lead tetraacetate in benzene at room temperature (equation I). Thallium(lll) nitrate (4, 496) has also been used for this modified Willgerodt-Kindler reaction. 

Another sulphur nucleophile, 2-mercaptobenzimidazole, gave similarly 2-phen-acylthio-benzimidazole [29]. Acetophenones on treatment with methanolic HTI underwent rearrangement affording methyl arylacetates, Ar H2C02Me the same compounds were obtained with iodosylbenzene in acidic methanol (Section 5.2.3). 

Mono-C-Methylation of Arylacetonitriles and Methyl Arylacetates by Dimethylcarbonate A General Method for the Synthesis of Pure 2-Arylpropionic Acids. 

Acetophenones - methyl phenylacetates, ArCOCH3 -- ArCH2COOCH, Treatment of an acetophenone with thallium(Ill) nitrate in methanol containing a trace of perchloric acid at room temperature for 2-18 hr. results in formation of a methyl arylacetate in 60-95 % yield. The mechanism suggested for this transformation is shown in the formulation. The reaction provides an alternative to the Willgerodt-Kindler reaction."... 

MONO-C-METHYLATION OF ARYLACETONITRILES AND METHYL ARYLACETATES BY DIMETHYL CARBONATE, 76, 169... 

Monomethylation of Arylacetonitriles and Methyl Arylacetates with Dimethyl Carbonate. a Hydrolysis of 2-Arylpropionitriles and Methyl 2-Arylpropionates to 2-Arylpropionic Acids. b... 

FLUORO-2-PHENYLPROPANE, represents another route to a number of monofluorinated compounds. The mono-C-methylation of arylacetonitriles and methyl arylacetates by dimethyl carbonate as a route to 2-arylpropionic acids is exemplified by the synthesis of 2-PHENYLPROPIONIC ACID, the simplest member of an important class of anti-inflammatory agents. 

Pietro Tundo, Maurizio Selva, and Andrea Bomben 169 MONO-C-METHYLATION OF ARYLACETONITRILES AND METHYL ARYLACETATES BY DIMETHYL CARBONATE A GENERAL METHOD FOR THE SYNTHESIS OF PURE 2-ARYLPROPIONIC ACIDS. 2-PHENYLPROPIONIC ACID... 

Methylation of activated toluenes. Arylacetonitriles and methyl arylacetates are monomethylated at the benzylic position on heating with (MeO)2CO and K2COJ in an autoclave at I80°C. 

The unusually high selectivity observed in the monomethylation of methyl aryloxyacetates and aryloxyacetonitriles may be explained by the mechanism previously described for the reaction of DMC with methyl arylacetates and arylacetonitriles (6) in which ArCH(COOCH3)X and ArC(CH3)(COOCH3)X are the key intermediates. It is likely that this reaction proceeds through the formation of methyl-carboxymethyl intermediates, ArOC(CH3)(COOCH3)X, as these derivatives were actually detected by GC/MS during the course of the reaction. In this case, the attack on the acyl carbon, which produce the possible intermediate PhC(COOCH3)2X, does not affect selectivity, because it is an equilibrium reaction. 

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