Crowded triarylphosphines have attracted broad interest for a long time since they have unique structure, properties, and reactivity. This review article focuses on synthesis, structure, properties, and application of crowded triarylphosphines represented by trimesitylphosphine and tris(2,4,6-triisopropylphenyl)phosphine, which are of interest from contemporary viewpoint of material science rather than ligands for transition metal catalysis. Synthesis of the crowded triarylphosphines by reaction of various aryl organometallic reagents with phosphorus halides, structures of the crowded triarylphosphines in solid and solution, redox properties and structure-property relationship, cation radicals of crowded triarylphosphines, and construction of the functional molecules carrying crowded triarylphosphines are described.
Keywords: borylphosphinobenzenes, Redox process, cation radicals, oxidation potentials, aminophosphinobenzenes