From chiral and prochiral N-allylpyrroles to stereodefined pyrrole fused architectures: A particular application of the rhodium-catalyzed hydroformylation

We review our recent results on the rhodium-catalyzed hydroformylation of chiral and prochiral N-allylpyrroles as a synthetic route to stereodefined 5,6-dihydro- and 5,6,7,8-tetrahydroindolizines. The indolizine nucleus at different degrees of unsaturation is a building block of natural and synthetic target compounds; thus new approaches, especially if stereoselective and/or stereospecific, are highly desirable. The construction of the indolizine architectures reported here occurs by formation of a C8–C9 bond through intramolecular cyclization of the 4-pyrrolylbutanal intermediate.

Graphical abstractA short review is given on the rhodium-catalyzed hydroformylation of chiral and prochiral N-allylpyrroles as a synthetic route to stereodefined 5,6-dihydro- and 5,6,7,8-tetrahydroindolizines. In the key step, the carbonyl group of a 4-pyrrolylbutanal, the oxo product, becomes the starting point for an intramolecular cyclization reaction generating the C8–C9 indolizine bond.Figure optionsDownload full-size imageDownload as PowerPoint slide