Fluoro(trifluoromethyl)phosphorus(V) derivatives with the pentane-2,4-dionato ligand (acetylacetone) of the general formula F4-x(CG3)x [formula omitted] (x = 1-3) and CH3(CF3)3[formula omitted] have been prepared and compared to the known F4P(acac) (i.e., x = 0). All are stable crystalline solids with a six-coordinate phosphorus geometry as illustrated by the characteristic high-field31P NMR chemical shifts and the19F and31P coupling constant patterns. The six-coordinate nature of these derivatives is further substantiated by the crystal and molecular structures of F2(CF3)2[formula omitted] (III) and F(CF3)3[formula omitted] (IV). Crystal data for III: orthorhombic, space group Pbca (No. 61), a = 12.323 (4) Å,b = 22.871 (5) Å, c = 7.505 (5) Å, V = 2115 Å3, Z = 8. Final R and Rwvalues for III were 0.090 and 0.105, respectively. The molecular structure of III shows that the acac ligand is essentially planar and that the two F and acac substituents lie in the same plane about the six-coordinate phosphorus atom. Crystal data for IV: monoclinic, space group P21/c (No. 14), a = 10.218 (1) Å, b = 8.822 (3) Å, c = 13.930 (7) Å, β = 107.21 (3)°, V = 1196 Å3, Z = 4. Final R and Rwvalues for IV were 0.047 and 0.070, respectively. The molecular structure of IV shows that the unique F occupies a position perpendicular to the central plane, which comprises two of the CF3groups and the two oxygen atoms of the acac ligand. The acac ligand is planar but is folded about the O–O axis by approximately 27° toward the unique fluorine. Infrared, mass, and ultraviolet spectra are reported for the compounds.
|Number of pages||8|
|Publication status||Published - 1 Mar. 1987|