Phosphorus-containing heteroarenes

Figure 12.15 Six-membered phosphorus-containing heteroarenes (E —lone pair, S, O).

Recently the diketo-ring systems have been expanded to include other phosphorus-containing heteroarenes for organic electronic applications. 

In the context of heteroarenes, five-membered rings containing phosphorus occur in many forms. The most common species is phosphole, the analog to pyrrole and thiophene, which contains a butadiene fragment bridged with a phosphorus functional group. Because of the pyramidal geometry of the phosphorus center. 

An alternative strategy for modifying heteroarenes containing five-membered phosphorus rings is via the incorporation of another heteroatom directly into the cyclic scaffold (Figure 12.14) [27, 28]. The general synthesis of these is shown... 

Figure 12.23 Backbone-extended heteroarenes containing diketo phosphorus rings.

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