Synthesis of N-Methylpyrrole and N-Methylimidazole Amino Acids Suitable for Solid-Phase Synthesis was written by Jaramillo, David;Liu, Qi;Aldrich-Wright, Janice;Tor, Yitzhak. And the article was included in Journal of Organic Chemistry in 2004.Name: Methyl 4-bromo-1-methyl-1H-pyrrole-2-carboxylate This article mentions the following:
New and higher yielding synthetic routes to Boc-protected N-methylpyrrole and N-methylimidazole amino acids are introduced to circumvent difficulties associated with established schemes. Key step in the synthesis of pyrrole amino acid I was copper-mediated cross-coupling reaction of Me 4-bromo-N-methyl-2-pyrrolecarboxylate with tert-Bu carbamate to directly install a carbamate-protected amino group. Key step in the synthesis of imidazole amino acid II was nitration of 1-methyl-2-(trichloroacetyl)imidazole followed by a one-pot reduction/Boc protection of the amine. In the experiment, the researchers used many compounds, for example, Methyl 4-bromo-1-methyl-1H-pyrrole-2-carboxylate (cas: 1196-90-3Name: Methyl 4-bromo-1-methyl-1H-pyrrole-2-carboxylate).
Methyl 4-bromo-1-methyl-1H-pyrrole-2-carboxylate (cas: 1196-90-3) belongs to organobromine compounds. Bromine is more electronegative than carbon (2.9 vs 2.5). Consequently, the carbon in a carbon–bromine bond is electrophilic, i.e. alkyl bromides are alkylating agents. Bromine-containing agents predominate because not only are they more efficient than similar chlorine-containing species, but also the high atomic weight of bromine ensures that it is present in a high mass fraction within most organobromine compounds.Name: Methyl 4-bromo-1-methyl-1H-pyrrole-2-carboxylate
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary