Compounds Featuring the Structural Fragment P-C-P

Abstract

This article summarizes some of our investigations of compounds featuring the structural fragment P‒C‒P. Phosphorus atoms in different oxidation states and coordination numbers display different chemical behaviors. This may lead to unique chemical properties when they are bridged by a methylene group in a P‒CH₂‒P system. For example, the P^III‒CH₂‒P^Vunit is able to add different unsaturated compounds to give zwitterionic products with oppositely charged phosphorus atoms. In addition, the two hydrogen atoms in P‒CH₂‒P may also take part in different transformations, resulting in the formation of carbodiphosphoranes or in the formation of a direct P-P bond to give three-membered ring diphosphiranes.

Keywords:

• Azaphospholes
• diphosphiranes
• hypervalency
• phosphanes
• ylides
• zwitterions

Acknowledgments

We thank the Alexander von Humboldt Foundation, the Swiss National Science Foundation, the Deutsche Forschungsgemeinschaft, and the Ukrainian Academy of Sciences for support of these investigations.