Phosphinidenes: Fundamental Properties and Reactivity

Abstract

Phosphinidenes are heavy congeners of nitrenes that have been broadly used as in situ reagents in synthetic phosphorus chemistry and also serve as versatile ligands in coordination with transition metals. However, the detection of free phosphinidenes is largely challenged by their high reactivity and also the lack of suitable synthetic methods, rendering the knowledge about the fundamental properties of this class of low‐valent phosphorus compounds limited. Recently, an increasing number of free phosphinidenes bearing prototype structural and bonding properties have been prepared for the first time, thus enabling the exploration of their distinct reactivity from the nitrene analogues. This Concept article will discuss the experimental approaches for the generation of the highly unstable phosphinidenes and highlight their distinct reactivity from the nitrogen analogues so as to stimuate future studies about their potential applications in phosphorus chemistry.

Spectroscopic Identification of Trifluorosilylphosphinidene and Isomeric Phosphasilene and Silicon Trifluorophosphine Complex

“…As low-valent phosphorus species, they have been widely used in synthetic chemistry as in situ phosphorus agents − or as ligands in transition metal complexes . Due to their high reactivity and instability, fundamental knowledge about phosphinidenes is mainly achieved by trapping and complexation experiments. − In contrast to the free nitrenes and carbenes, which have been extensively investigated, only a handful of uncomplexed phosphinidenes have been experimentally identified (Scheme ). The parent phosphinidene (H–P) ( 1 ) was observed in the argon matrix following the photolysis of phosphaketene, HPCO .…”

Carbamoylphosphinidene: A Phosphorus Analogue of Carbonyl Nitrene

“…Phosphinidenes are electrophilic intermediates that have been widely used as in situ reagents for phosphorus-atom transfer reactions . Recently, a number of simple phosphinidenes have been spectroscopically characterized, and they were generated through photodecomposition of the corresponding phosphaketenes, phosphiranes, or azide precursors .…”