Phospha-Organic Chemistry: Panorama and Perspectives

Since the beginning of the seventies, organophosphorus chemistry has been completely rejuvenated by the discovery of stable derivatives in which phosphorus has the coordination numbers one or two. The chemistry of these compounds mimics the chemistry of their all‐carbon analogues. In this Review article this analogy is discussed for the phosphorus counterparts of alkenes, alkynes, and carbenes. In each case, the synthesis, reactivity, and coordination modes are briefly examined. Some special electronic configurations are also discussed, which include one‐electron PP bonds, strained bonds, and aromatic systems. To conclude, some potential applications of this chemistry in the areas of molecular materials and homogeneous catalysis are presented. The great pretender: Phosphorus mimics quite closely the chemistry of carbon in its low coordination states (that is, one and two). The picture illustrates some of the molecules which highlight this analogy: clockwise from the top: phosphaacetylene, phosphirane, phosphinine, the transient phosphinidene complex [HP‐W(CO)5], phosphaferrocene, phosphole, and phosphaethene.