Chapter 3: Air-stable, fluorescent primary phosphines¹

This article reviews recent findings from our research group on the preparation and utility of fluorescent primary phosphines based on the boron dipyrromethene (Bodipy) skeleton. Remarkably, these new phosphines are air-stable in both the neat state and in solution, by virtue of the extended conjugation in the Bodipy backbone – these findings are also in agreement with our DFT model. The ligands’ optical properties and their coordination to molybdenum carbonyl complexes are investigated; interestingly the presence of the −PH₂ moiety on the Bodipy dye has a minimal effect on the absorption and emission profile of both the ligands and their transition metal complexes. The primary phosphines also undergo the hydrophosphination reaction to give fluorescent tridentate ligands and subsequently rhenium complexes, which are attractive analogues of dual diagnostic imaging agents. Finally, the current status of Bodipy phosphine dyes is reviewed.