Unveiling the N‐Nucleophilicity of Non‐Aromatic Pyrroles Through Rhodium Catalysis: A Case of Synthesis and Luminescence Studies of Pyrrolo[2,1‐a]isoquinolinium Salts

Abstract

AbstractAn expedient synthesis of hitherto unknown pyrrolo[2,1‐a]isoquinolinium salts from non‐aromatic aryl‐substituted 2H‐ and 3H‐pyrroles and internal alkynes has been developed. The process represents a rare example of N‐nucleophilic reaction of 2H‐ and 3H‐pyrroles and relies on theortho‐C−H bond activation of non‐aromatic arylpyrroles in the presence of rhodium catalyst followed by alkyne annulation reaction. A broad range of diversely substituted salts was obtained in high yields under mild reaction conditions. The photophysical properties for selected representatives of novel pyrrolo[2,1‐a]isoquinolinium salts have been evaluated to demonstrate their potential as fluorescent materials for light‐emitting devices and bioimaging.