| 19408931 |
Sarkar B, Wen SY, Wang JH, Chiou LS, Liao PK, Santra BK, Wang JC, Liu CW: Conjugate base of a secondary phosphine selenide [P (Se)(O (i) Pr) 2]- as the bridging unit for the construction of heterometallic Fe (II)-Hg (II)/Cd (II) complexes. Inorg Chem. 2009 Jun 15;48(12):5129-40.
Reactions of perchlorate salts of Hg (II)/Cd (II) with [CpFe (CO)(2) P (Se)(O (i) Pr)(2)] (denoted as L) produced dicationic clusters [HgL (2)](ClO (4))(2), 1; [HgL (3)](ClO (4))(2), 2; and [CdL (3)(H (2) O)](ClO (4))(2), 11. However, the reactions of L with Hg (II)/Cd (II) halides yielded neutral complexes. For instance, HgI (2) produced [Hg (3) I (6) L (2)], 3, or [HgI (2) L (2)], 4, depending on the metal-to-ligand ratio used. Reaction of L with any of the Hg (II)/Cd (II) halides in a 1:1 ratio produced neutral clusters [HgX (mu-X) L](2) (M = Hg; X = Cl, 5; Br, 6; I, 7; M = Cd; X = Cl, 8; Br, 9; I, 10). Thus, variation of the M-to-L ratio made it possible for the formation of compounds with different metal/ligand stoichiometries only when ClO (4)(-) and I (-) salts of Hg (II) were used. Single-crystal X-ray crystallography revealed that two and three L units were connected to a Hg (II) via its Se atom in 1 and 2, respectively, whereas Hg (II) in 4 was connected to two "I" and two "L" units. An L (through its Se) and a terminal halogen were attached to each of the Hg (II)'s of the Hg (2) X (2) parallelogram core in 5 and 6. The cadmium complex 8, with a Cd (2) Cl (2) parallelogram core, was isostructural with the mercury complex 5. Although bonding and connectivity in 8 were similar to those in 9 and 10, the conformation of the bulky L ligands was unusually syn in 9 and 10, unlike the anti orientation in 5, 6, and 8. The syn conformation of L was also observed in compounds 1 and 2. Secondary interactions, namely, Se...Se interaction, the X...H-C type of H-bonding (X = halogen or Se), and pi-stacking, revealed in the structures played a role in determining the ligand conformation. The [P (Se)(O (i) Pr)(2)](-), the conjugate base of secondary phosphine selenide [HP (Se)(O (i) Pr)(2)], acted as a bridge with P bonded to Fe and Se bonded to Hg (or Cd) in these heterometallic clusters. Compound 5 further demonstrated a longer P-Se bond in the secondary phosphine selenide compared to that in isostructural, tertiary phosphine selenide metal complexes. |
1(0,0,0,1) |