Phenylpyrazole-based hypervalent

In a more recent work, Kornev and coworkers reported the preparation and structural studies of a series of phenylpyrazole-based hypervalent phosphorus compounds 34 and 35 (Figure 8), which represent another example of low-coordinate hypervalent phosphorus heterocycles (2015EJIC2057). According to X-ray structural data, the phosphorus atom in molecule 34 has overall trigonal bipyramidal geometry with chlorine atoms at the apical position, while the N- and C-substituents and the lone electronic pair are occupying the equatorial positions with P—N and P—C bond distances of 1.771 and 1.831 A, respectively. 

Figure 8 Phenylpyrazole-based hypervalent phosphorus heterocycles.

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