Functionalized Pentafluoroethylphosphanes

Allefeld N, Neumann B, Stammler H-G, Ignat'ev N, Hoge B. Functionalized Pentafluoroethylphosphanes. Chemistry - A European Journal. 2015;21(35):12326-12336.Bis(diethylamino)pentafluoroethylphosphane represents a versatile starting material for the synthesis of functionalized pentafluoroethylphosphanes. Perfluoroalkyl substituted aminophosphanes themselves already exhibit interesting coordination properties and were treated with the catalytically relevant salts PtCl2 and PdCl2 affording trans[Cl2M{P(C2F5)(NEt2)(2)}(2)]. The hitherto unknown (C2F5)PBr2, accessible in good yields by treatment of C2F5P(NEt2)(2) with HBr, was smoothly transformed into the corresponding phosphane, C2F5PH2, or fluoro derivative, C2F5PF2. Acidic hydrolysis of C2F5P(NEt2)(2) yielded the phosphinic acid C2F5P(O)(OH)H, the anion of which was structurally characterized. The phosphinic acid smoothly adds to the carbonyl group of acetone under P-C bond formation. An analogous reaction with aldehydes, for example, salicyl aldehyde, offers the possibility to generate stereocenters