Synthesis of Tri-and Tetracoordinate Phosphorus Compounds Containing a PCF_3 Group by Nucleophilic Trifluoromethylation of the Corresponding PF Compounds

摘要

The introduction of a trifluoromethyl group into an organic compound can bring about remarkable changes in physical, chemical, and biological properties. Therefore, the importance of fluorinated compounds in life sciences is rapidly increasing. Modification of the backbone of biophosphates by replacement of the anionic phosphodiester group with the neutral trifluoromethylphosphonato group should have steric, polar, and electronic effects similar to those of a hydroxylgroup. Additionally, the lipophilicity should be enhanced. Tricoordinate P~III-CF_3 compounds may act as useful ligands in organometallic chemistry. Among the variety of methods for introducing a CF_3 group into organic compounds, the application of 9trifluoromethyl) trimethylsilane CF_SiMe_3 (1) as nucleophilic trifluoromethlating reagent is rapidly becoming the method of choice. CF_3SiMe_3 was first synthesized by Ruppert et al. in 1984 and is commercially available. In contrast to organic compounds containing a CF_3 group, little is known about P~III-CF_3 compounds. P~v-F compounds, which are apparent candidates for uncleophilic trifluoromethylation by 1, have been used for this purpose in only two cases. So far no reaction of this kind has been described for P~III-F compounds.