Cyclopenta[b]pyrroles from triazines: synthetic and mechanistic studies.
The pyrrolidine-mediated reactions of 3,5-disubstituted 1,2,4-triazines with cyclobutanone lead to cyclopenta[b]pyrroles, which can be derivatized into hydrazones and oximes. The cyclopenta[b]pyrrole ring system likely arises through a tandem [4 + 2] cycloaddition/cycloreversion/ring rearrangement reaction. In contrast, 3,6-disubstituted 1,2,4-triazines undergo a simple nucleophilic 1,4-addition with cyclobutanone to give 1:1 adducts.
Ye
Long
L
Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, USA.
Haddadin
Makhluf J
MJ
Lodewyk
Michael W
MW
Ferreira
Andrew J
AJ
Fettinger
James C
JC
Tantillo
Dean J
DJ
Kurth
Mark J
MJ