Regioselective synthesis of 2,3,4- or 2,3,5-trisubstituted pyrroles via [3,3] or [1,3] rearrangements of O-vinyl oximes was written by Wang, Heng-Yen;Mueller, Daniel S.;Sachwani, Rachna M.;Kapadia, Rachel;Londino, Hannah N.;Anderson, Laura L.. And the article was included in Journal of Organic Chemistry in 2011.Name: Ethyl 3-oxo-3-(m-tolyl)propanoate This article mentions the following:
The regioselective synthesis of 2,3,4- or 2,3,5-trisubstituted pyrroles e. g., I has been achieved via [3,3] and [1,3] sigmatropic rearrangements of O-vinyl oximes, resp. Iridium-catalyzed isomerization of easily prepared O-allyl oximes enables rapid access to O-vinyl oximes. Optimization and scope of the O-allyl oxime isomerization and subsequent pyrrole formation are discussed and mechanistic pathways are proposed. The regioselectivity of pyrrole formation can be controlled by either the identity of the α-substituent or through the addition of an amine base. When enolization is favored, a [3,3] rearrangement followed by a Paal-Knorr cyclization provides a 2,3,4-trisubstituted pyrrole; when enolization is disfavored, a [1,3] rearrangement occurs prior to enolization to produce a 2,3,5-trisubstituted pyrrole after cyclization. Conditions are provided for selecting either the [3,3] rearrangement or the [1,3] rearrangement product with β-ester O-allyl oxime substrates. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9Name: Ethyl 3-oxo-3-(m-tolyl)propanoate).
Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.Name: Ethyl 3-oxo-3-(m-tolyl)propanoate
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