Structural studies of steric effects in phosphine complexes. Part 3. The synthesis, characterization, and molecular structure of diacetato[tris(t-butyl)phosphine]mercury(II)

Abstract

The title complex has been synthesized and found to crystallize in the monoclinic space group P2₁/c with a= 12.326(5), b= 10.938(3), c= 16.005(3)Å, and β= 111.16(1)°. The structure has been solved from diffractometer data using Patterson and Fourier techniques and refined by least-squares methods to a final R of 0.049 for 1 478 independent observed reflections. The geometry at the mercury atom is distorted trigonal bipyramidal with three strong bonds forming a trigonal plane [Hg–P 2.371 (4). Hg–O(2) 2.25(1), and Hg–O(4) 2.27(1)Å] and the remaining oxygens of the asymmetrically bidentate acetate groups above and below this plane [Hg–O(1) 2.66(2) and Hg–O(3) 2.58(1)Å]. Other mean dimensions include P–C 1.90(2)Å, Hg–P–C 106.8(5)°, and C–P–C 112.0(7)°. A ligand profile for PBu^t₃ is given and the maximum cone angle for the ligand is 187(2)°.