Studies on the efficient generation of phosphorus-carbon bonds via a rearrangement of P(III) esters catalysed by trimethylhalosilanes.

Halotrimethylsilanes Me(3)SiX (X = Br, I) catalyse rearrangements of tricoordinate phosphorus esters R'R''P-OR into the corresponding phosphoryl systems R'R''P(O)R. This provides a simple and efficient route to a variety of structures containing phosphorus-carbon bonds, under mild conditions and with good yields. The reaction mechanism was investigated in detail by (31)P NMR spectroscopy and independent synthesis of the reaction intermediates.

Synthesis of phosphorofluoridates and phosphorofluoridothioates via the phosphoramidite approach.

We present a very efficient synthetic procedure leading to the phosphorofluoridates RO-P(O)(OH)F 1 or phosphorofluoridothioates RO-P(S)(OH)F 2, which is based on the intermediary of fluorophosphoramidites (RO)P(F)N(i)Pr2 5 [R = 9-(hydroxyethyloxymethyl)guaninyl), 3'azido-3'deoxythymidinyl, thymidinyl, anhydrothymidinyl, cholesteryl, N6-benzoyl-5'-O-(4,4'-dimethoxytrityl)-2'-deoxyadenosinyl]. The activation of the amino group was performed with trimethylchlorosilane (TMCS).

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

A new way of forming P-C bonds: Catalytic amounts of F ions facilitate the reaction of P -F compounds with CF SiMe to give P -CF compounds. These compounds can also be obtained in a one-pot procedure from P -OAr precursors (also shown).