Rh(iii)-Catalysed synthesis of cinnolinium and fluoranthenium salts using C-H activation/annulation reactions: organelle specific mitochondrial staining applications.

The construction of a novel class of indazolo[2,1-a]cinnolin-7-ium and diazabenzofluoranthenium salts was developed by using Rh(iii)-catalyzed C-H activation/annulation reactions with 2-phenyl-2H-indazole, and internal alkynes, which resulted in structurally important polycyclic heteroaromatic compounds (PHAs). This reaction uses mild reaction conditions and has a high efficiency, low catalyst loading, and wide substrate scope. The overall catalytic process involves C-H activation followed by C-C/C-N bond formation. Furthermore, the synthesised cinnolinium/fluoranthenium salts exhibit potential fluorescence properties and 5i was targeted in particular for specific mitochondrial staining in order to investigate cancer cell lines.

Ru(II)-Catalyzed Regiospecific C-H/O-H Oxidative Annulation to Access Isochromeno[8,1-ab]phenazines: Far-Red Fluorescence and Live Cancer Cell Imaging.

A facile ruthenium(II)-catalyzed regiospecific C-H/O-H oxidative annulation methodology was developed to construct isochromeno[8,1-ab]phenazines. This methodology delivers various advantages, such as scope for diverse substrates, tolerance to a range of functional groups, stability under air, and yields regioselective products. This methodology was successfully applied to synthesize far red (FR) fluorescent probes for live cancer cell imaging. The synthesized compounds displayed notable fluorescence properties in solution and thin-film. Their application in live cancer cell imaging was investigated using various cancer cell lines. The synthesized compound showed prominent FR fluorescence, with high quantum yield, and exhibited better cell-imaging properties, with excellent biocompatibility.