Selenones, synthetic applications

There are only few hexavalent selenium compounds of interest to synthetic chemists. Selenonic acids 198 and selenones 199 have found several synthetic applications, whereas the organic synthesis of perselenuranes such as phenylselenenyl pentafluoride 200 still remains unexplored. (Figure 8).344... 

Selenonic acids 194a and selones 194b belong to the best-known hexavalent, tetracoordinated organoselenium compounds. Moreover, they have found synthetic applications in recent years. 

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