A process for preparing methyl 2-(4-bromophenyl)-2-methylpropanoate is disposed in J. Org. Chem. 1994, 59, 2620-2622. Herein, methyl 2-(4-bromophenyl)-2-methyl propanoate is prepared by esterification of 4-bromophenylacetic acid followed by methylation of the benzylic carbon employing 2.4 equivalents of methyl iodide in the presence of sodium hydride in a tetrahydrofuran medium. However, the process of selective bromination either from phenyl acetic acid or from 2-methyl-2-phenylpropanoic acid is not described. The efforts of the present inventors did not result in industrial application of this process due to the following drawbacks:
1) Preparation of 4-bromophenylacetic acid requires multistep synthesis.
2) Trimethyl chlorosilane and methyl iodide reagents are expensive to use on commercial scale.
3) Sodium hydride is a highly flammable material and an industrially hazardous reagent.
4) Tetrahydrofuran used as a solvent is also expensive to use on a commercial scale.
5) The reaction is highly exothermic.
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