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Examines the preparation of one-dimensional arrays {(DMF)10Yb2[Ni(CN)4]3} and {(DMF)10Yb2[Pt(CN)4]3} from the metathesis reaction of YbC13 and K2Ni(CN)4 of K2Pt(CN)4 in DMF (DMF = N,N-dimethylformamide.) What was obtained from the preparation.

Abstract: New lanthanide−transition metal (Ln–M) carbonyl compounds were prepared and the structural relationships of the metal combinations were discerned. Numerous compounds derived from combinations of divalent lanthanides with transition metal carbonyls in groups 7–9 were isolated. Three different types of interactions were observed: (1) Ln–M direct bonds, (2) ionic associations, and (3) carbonyl or cyanide linkers between the metals. These assorted Ln–M interactions influence the assembly of the compounds, and discrete molecules or polymeric arrays were encountered. The extended arrays formed from isocarbonyl linkages can function as heterogeneous catalyst precursors. To cite this article: S. Liu et al., C. R. Chimie 8 (2005) . [Copyright &y& Elsevier]

Examines the effect of hydrogen bonding on the structure of sheet- and column-like cyanide-bridged lanthanide-transition metal array complexes when potassium is replaced by an ammonium compound by single-crystal X-ray analysis. Bond lengths and angles; Sheet structure of isomorphous and isostructural complexes; Coordination geometry of europium and ytterbium.

Examines evidence for the O-H...NC hydrogen bonding in a lanthanide-transition-metal complex [H(sub 2)O](sub 6][DMF](sub 6-)Ho(sub 2)[Ni(CN)(sub 4)](sub 3). Bicapped trigonal prismatic coordination geometry of the complex around holmium; Presence of strong to moderate O-H...NC hydrogen bonds between oligomers; Presence of multiple hydrate water molecules.

Water-free rare earth(III) hexacyanoferrate(III) complexes, (Ln(DMF)[sub6](μ-CN)[sub2]Fe(CN)[sub4])[sub∞](DMF = N,N-dimethylformamide; Ln = Sm, 1; Eu. 2; Gd, 3; Tb, 4; Dy, 5; Ho, 6; Er, 7; Tm, 8; Yb, 9; Lu, 10; Y, 11; La, 12; Ce, 13; Pr, 14; Nd, 15), were synthesized in dry DMF through the metathesis reactions of [(18-crown-6)K][sub3]Fe(CN)[sub6] with LnX[sub3](DMF)[subn] (X = Cl or NO[sub3]). Anhydrous DMF solutions of Ln[sub3](DMF)[subn] were prepared at room temperature from LnCl[sub3] of LnX[sub3] ∙ nH[sub2]O under a dynamic vacuum. All compounds were characterized by IR, X-ray powder diffraction (except for 10), and single crystal X-ray diffraction (except for 2, 7, 10). Infrared spectra reveal that a monotonic, linear relationship exists between the ionic radius relationship. X-ray powder diffraction data are in agreement with powder patterns calculated from single crystal X-ray diffraction results, a useful alternative for bulk sample confirmation when elemental analysis data are difficult to obtain. Eight-coordinate Ln(III) metal centers are observed for all structures. trans-cyanide units of [Fe(CN)[sub6]][sup3-] formed isocyanide linkages to Ln(III) resulting in one-dimensional polymeric chains. Structures of compounds 1-9 and 11 are isomorphous, crystallizing in the space group C2/c. Structures of compounds 12-15 are also isomorphous, crystallizing in the space group P2/n. One unique polymeric chain exists in the structures of 1-9 and 11 while two unique polymeric chains exist in structures of 12-15. One of the polymeric chains of 12-15 is similar to that observed for 1-9, 11 while the other is more distorted and has a shorter Ln-Fe distance. Magnetic susceptibility measurements for compounds 3-6, 8, 11 were performed on polycrystalline samples of the compounds. [ABSTRACT FROM AUTHOR]

New solvent-separated ion-pair compounds and extended structures containing ytterbium(II)-transition metal isocarbonyl linkages were synthesized. [Yb(THF)8][M(CO)5]2 (1, M = Mn; 2, M = Re) were prepared via transmetalation reactions between Yb metal and Hg[M(CO)5]2 in THF. Reflux of 1 in Et2O afforded {Yb(THF)2-(Et2O)2[(μ-CO)2Mn(CO)3]2}∞ (3) which is a sheet-layer structure. In ether solution, 3 is converted to {Yb(THF)4-[(μ-CO)2Mn(CO)3]2}∞ (4) which has a linear structure. In both 3 and 4, ytterbium is 8-coordinated (distorted square antiprism geometry), four coordination sites occupied by molecules of solvent and four more by oxygen atoms of isocarbonyl linkages. The [Mn(CO)5]- anion has trigonal bipyramidal geometry and is linked to ytterbium through two equatorial carbonyls. The formation of two minor products, (THF)2Mn3(CO)10 (5) and [(THF)5Yb(μ-CO)Mn3-(CO)13][Mn3(CO)14] (6), was observed during condensation of 1 into 3 and 4. [ABSTRACT FROM AUTHOR]

Abstract: Systematic synthetic procedures produced several different structural types of extended lanthanide–transition metal (group 10) complexes with cyanide bridges. Of these, one-dimensional ladder arrays containing a Yb–Pd combination have been converted to bimetallic heterogeneous catalysts on an oxide (SiO2) surface that is more effective than supported Pd alone. Two lanthanide–Cu(I) complexes have been prepared. One type, an inclusion complex consists of lanthanide(III) cations encapsulated in the pockets of a three-dimensional anionic array that contains Cu(I)–CN–Cu(I) bridges. The second type, an extended layer complex, consists of joined five-membered rings in a “tile-like” pattern with Ln–CN–Cu and Cu–CN–Cu bridges. [Copyright &y& Elsevier]

The divalent lanthanide bis((cyclooctane-l,5-diyl)dihydroborate) complexes {K(THF)4}2{Ln{(μ-H)2BC6H14}4} (Ln = Eu, 3; Yb, 4) were prepared by a metathesis reaction between (THF)xLnCl2 and K[H2BC8H14] in THF in a 1:4 molar ratio. Although the reaction ratios were varied between 1:3 and 1:6, complexes 3 and 4 were the only lanthanide 9-BBN hydroborates produced. Because of disorder of THF in crystals of 3 and 4, good single-crystal X-ray structural data could not be obtained. However, when the potassium cation was replaced by the tetramethylammonium cation or when MeTHF (2-methyltetrahydrofuran) was employed in place of THF, good quality crystals were obtained. Complexes [NMe4]2[Ln{(μ-H)2BC8H14}4] (Ln = Eu, 5; Yb, 6) were afforded by metathesis reactions of NMe4Cl with 3 and 4 in situ. On the basis of the single-crystal X-ray diffraction analysis, the four 9-BBN tetrahydroborate ligands are tetrahedrally arranged around the lanthanide cation in 5 and 6. The two structures differ in that one α-C-H bond from each of the four {(μ-H)2BC8H14}4 units exhibits an agostic interaction with Eu(II) in 6 but, in complex 6, only two of the α-C-H bonds form agostic interactions with Yb(II). Complexes {K(MeTHF)3}2{Ln{(μ-H)2BC8H14}4} (Ln = Eu, 7; Yb, 8) were produced by employing MeTHF in place of THF. The structures of 7 and 8 display connectivity between the anion {Ln{(μ-H)2BC8H14}4}2- and the cation {K(MeTHF)3}+, in which the potassium not only interacts directly with the hydrogens of the Ln-H-B bridged bonds but is also involved in agostic interactions with α-C-H bonds. By systematically examining the structures of complexes 3–8 and taking into account the previously reported complexes (THF)4Ln{(μ-H)2BC8H14}2 (Ln = Eu, 1; Yb, 2), it is concluded that Eu(II) appears to have a better ability to form agostic interactions than Yb(II) because of its larger size, even though Yb(II) has a higher positive charge density. [ABSTRACT FROM AUTHOR]

Two types of Ln(II)-Co[SUB4] isocarbonyl polymeric arrays, {(Et[SUB2]O)[SUB3-x](THF)[SUBx]Ln[Co[SUB4](CO)[SUB11]]}[SUB∞] (1-3; x = 0, 1) and {(THF)[SUB5]Eu[Co[SUB4](CO)[SUB11]]}[SUB∞] (4), were prepared and structurally characterized. Transmetalation involving Ln(0) and Hg[Co(CO)[SUB4]][SUB2] in Et[SUB2]O yields {(Et[SUB2]O)[SUB3]Ln[Co[SUB4](CO)[SUB11]]}[SUB∞ (1, Ln = Yb; 2, Ln = Eu). Dissolution of the solvent-separated ion pairs [Ln(THF)[SUBx]][Co(CO)[SUB4]][SUB2] (Ln = Yb, x = 6; Ln = Eu) in Et[SUB2]O affords {(Et[SUB2]O)[SUB2]-(THF)Yb[Co[SUB4](CO)[SUB11]]}[SUB∞] (3) and {(THF)[SUB5]Eu[Co[SUB4](CO)[SUB11]]}[SUB∞](4). In these reactions, oxidation and condensation of the [Co(CO)[SUB4]][SUP-] anions result in formation of the new tetrahedral cluster [Co[SUB4](CO)[SUB11]][SUB2-]. The two types of Ln(II)-Co[SUB4] compounds contain different isomers of [Co[SUB4](CO)[SUB11]][SUP2-], and, consequently, the structures of the infinite isocarbonyl networks are distinct. The cluster in {(Et[SUB2]O)[SUB3-x](THF)[SUBx]Ln[Co[SUB4](CO)[SUB11]]}[SUB∞] (1-3) possesses pseudo C[SUB3v] symmetry (an apical Co, three basal Co atoms; one face-bridging, three edge-bridging, seven terminal carbonyls) and connects to Ln(II) centers through η[SUP2], μ[SUB4-]- and η[SUP2],μ[SUB3]-carbonyls to generate a 2-D puckered sheet. In contrast, {(THF)[SUB5]Eu[Co[SUB4](CO)[SUB11]]}[SUB∞] (4) incorporates a C[SUB2v] symmetric cluster (two unique Co environments; two face-bridging, one edge-bridging, eight terminal carbonyls), and isocarbonyl linkages (η[SUP2],μ[SUB4]-carbonyls) to Eu(II) atoms create a 1-D zigzag chain. Complexes 1-4 contain the first reported η[SUP2],μ[SUB4]-CO bridges between a Ln and a transition-metal carbonyl cluster. Infrared spectroscopic studies revealed that the isocarbonyl associations to Ln(II) persist in solution. [ABSTRACT FROM AUTHOR]

Describes the synthesis and characterization of a series of one-dimensional arrays of lanthanide-transition metal complexes. Cyanide-bridged lanthanide(III), or rare earth,-transition metal extended arrays; Interconversion of one-dimensional arrays from single-strand to double-strand structures; Complexes of a novel type of single-strand array.