A. Nikitenko, M. Winkley, Joseph Zeldis
Jun 2, 2006
Citations
0
Influential Citations
19
Citations
Journal
Organic Process Research & Development
Abstract
The isomeric mixture of ethyl 5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole-2- and −3-carboxylates (14 and 15), derived from a proline meso-ionic synthon, demonstrated remarkably different stabilities towards alkaline hydrolysis. On that basis, a nonchromatographic, highly efficient method for their large-scale separation was developed. The desired isomer 14 was converted into 5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole-2-carbaldehyde, a key intermediate in the synthesis of bicyclic heteroaryl-substituted 6-alkylidene penems.