110466-50-7Relevant articles and documents
THE SYNTHESIS AND CHEMISTRY OF AZOLENINES. PART 12. ISOLATION OF INTERMEDIATE 2-HYDROXY-3,4-DIHYDRO-2H-PYRROLES IN THE PAAL-KNORR 1H-PYRROLE SYNTHESIS.
Chiu, Pak-Kan,Sammes, Michael P.
, p. 3531 - 3538 (2007/10/02)
Treatment of 1,4-diketones with liquid ammonia gives high yields of isolable 2-hydroxy-3,4-dihydro-2H-pyrrole intermediates.These intermediates, which do not appear to have been observed previously in the Paal-Knorr synthesis with ammonia, have been fully characterized by i.r. and 1H and 13C n.m.r. spectroscopy; in most cases they decompose quantitatively into 1H-pyrroles on standing.The intermediate from hexane-2,4-dione may also be prepared using concentrated aqueous ammonia.
Novel Synthesis of 3H-Pyrroles, and Novel Intermediates in the Paal-Knorr 1H-Pyrrole Synthesis: 2-Hydroxy-3,4-dihydro-2H-pyrroles from 1,4-Diketones and Liquid Ammonia
Chiu, Pak-Kan,Lui, Kon-Hung,Maini, Prem Nath,Sammes, Michael P.
, p. 109 - 110 (2007/10/02)
Reaction of 2,2-dimethyl-1,4-diketones with liquid ammonia gives high yields of isolable 2-hydroxy-3,4-dihydro-2H-pyrroles (3) and (5) which are readily dehydrated to give separable mixtures of 3H-pyrroles and methylenedihydropyrroles, while less-substituted 1,4-diketones give analogous hydroxy-compounds (4) and (6) which are hitherto-unsuspected intermediates in the Paal-Knorr 1H-pyrrole synthesis.
