Easy α- to β-migration of an enol moiety on a pyrrole ring

Authors :: Trofimov, Boris A.
Petrova, Ol’ga V.
Sobenina, Lyubov’ N.
Ushakov, Igor’ A.
Mikhaleva, Al’bina I.
Rusakov, Yurii Yu.
Krivdin, Leonid B.
Source :: Tetrahedron Letters: International Organ for the Rapid Publication of Preliminary Communications in Organic Chemistry. May2006, Vol. 47 Issue 22, p3645-3648. 4p.
Publication Year :: 2006
Abstract: Abstract: Functionalized pyrrolic enols, 2-(2,2-dicyano-1-hydroxyethenyl)-1-methylpyrroles, synthesized from 2-ethenylpyrroles by a nucleophilic SEt-OH exchange, upon heating (75–142°C) are readily rearranged to their 3-isomers in near to quantitative yield. The inter or intramolecular auto-protonation of a pyrrole ring by the acidic enol hydroxyl to form a mesomeric pyrrolium cation or zwitterion is suggested to be a key step in the rearrangement. [Copyright &y& Elsevier]

Subjects :: *PYRROLES
*HETEROCYCLIC compounds
*ORGANONITROGEN compounds
*CATIONS

Language :: English
ISSN :: 00404039
Volume :: 47
Issue :: 22
Database :: Academic Search Index
Journal :: Tetrahedron Letters: International Organ for the Rapid Publication of Preliminary Communications in Organic Chemistry
Publication Type :: Academic Journal
Accession number :: 20621887
Full Text :: https://doi.org/10.1016/j.tetlet.2006.03.148