Diverse 1,2- and 1,2,5-substituted pyrroles were efficiently prepared through a regioselective functionalization of 2-formylpyr-role (<strong>5a</strong>). This methodology was applied for the first total synthesis of pyrrolemarumine (<strong>4b</strong>), the aglycone of the corresponding natural pyr-role alkaloid 4”-O-a-L-rhamnopyranoside. The synthesis of <strong>4b</strong> was achieved starting from 5a through a seven-step process in 28% over-all yield.

A highly regio-, chemo- and stereoselective divergent synthesis of isoindolo- and pyrrolo-fused polycyclic indoles is herein described, starting from 2-formylpyrrole and employing Diels–Alder and Heck arylation reactions. 3-(N-Benzyl-2-pyrrolyl)acrylates and 4-(pyrrol-2-yl)butenones underwent a highly endo-Diels–Alder cycloaddition with maleimides to furnish octahydropyrrolo[3,4-e]indoles, which served as precursors in the regioselective synthesis of aza-polycyclic skeletons via an intramolecular Heck arylation reaction. Through the latter reaction, the 3-(N-benzyl-2-pyrrolyl)acrylates give rise to 3-(pyrrolo[2,1-a]isoindol-3-yl)acrylates. A further oxidative aromatization of the polycyclic intermediates provides the corresponding polycyclic pyrrolo-isoindoles and isoindolo-pyrrolo-indoles. A theoretical study on the stereoselective Diels–Alder reactions, carried out by calculating the endo/exo transition states, revealed the assistance of non-covalent interactions in governing the endo stereocontrol.

The selective functionalization of 2-formylpyrrole to provide diverse 1,2-and 1,2,5-substituted pyrroles is described. These compounds were used as versatile building blocks in a divergent synthesis of biologically valuable aza-bycyclic skeletons, such as pyrrolizine and pyrrolizidine derivatives. These bicycles were prepared following metalfree cascade synthetic approaches via regioselective intramolecular 1,3dipolar cycloadditions and stereoselective Knoevenagel/Michael/ cyclization with dimethyl malonate.

In this paper, the synthesis of two new chalcones with a donor-acceptor structure by Claisen-Schmidt condensation for photonic applications is presented. The characterization and evaluation of the optoelectronic properties are...