THE DEHYDRATION BEHAVIOR OF RARE-EARTH COMPLEXES OF M-NITROBENZOIC ACID

Rare earth complexes of m-nitrobenzoic acid (LnL3.2H2O, Ln = La-Lu and Y, except Pm, HL = m-nitrobenzoic acid) were synthesized and characterized by elemental analysis, chemical analysis, IR spectroscopy and X-ray diffraction analysis. The dehydration beh

CRYSTAL-STRUCTURES OF LN(NO3)(3) (LN=EU,LU) COMPLEXES WITH A CROWN-ETHER (16-CROWN-5)

The crystal structures of Ln(NO3)(3)(Ln = Eu,Lu) complexes with 16-crown-5 are reported. In [Eu(NO3)(2)(CH3CN)(16-crown-5)][Eu(NO3)(4)(H2O)2].1/2(16-crown-5) one Eu-III ion is coordinated to two bidentate nitrate ions, one acetonitrile molecule and five o

SYNTHESIS AND CHARACTERIZATION OF POLYMER-SUPPORTED LANTHANIDE COMPLEXES AND BUTADIENE POLYMERIZATION BASED ON THEM

Poly(styrene-acrylic acid)-lanthanide (Ln.PSAA) and poly(ethylene-acrylic acid)-neodymium (NdPEAA) complexes have been prepared and characterized. The infrared and X-ray photoelectron spectra indicate that the lanthanide complexes possess the bidentate carboxylate structure Ln-O-C(R)-O (see structure B in text). The catalytic behavior of the complexes has been described. The catalytic activities of Nd.PSAA and Nd.PEAA are much greater than that of the corresponding low molecular weight catalyst for butadiene polymerization. The activities of various individual lanthanide elements are quite different from one another. Neodymium shows the highest activity. Europium, samarium and the heavy elements exhibit very low or no activities. The cis-1,4 content of the polybutadiene obtained is not affected by different lanthanide elements in the series. The complex with the intermediate content of the functional group has a higher activity than the others. The polymer-supported lanthanide complexes having different constitutions have different catalytic activities. When the molar ratio of lanthanide to the functional group is ca. 0.2, the activity of the complex is in the optimum state. The activity is influenced by the dispersion of the lanthanide metal immobilized on the polymer chain. Catalytic activity can be improved by adding other metals to the catalyst system.

SYNTHESES, CHARACTERIZATION AND CRYSTAL-STRUCTURES OF THE COMPLEXES OF RARE-EARTH WITH O-CHLOROBENZOIC ACID

REL3.H2O (RE=Y, La is similar to Lu; HL = o-chlorobenzoic acid) were synthesized. Their thermal decomposition and IR spectra were studied. The crystal structures of the complexes of neodymium, terbium and lutetium were determined by X-ray diffraction method. They crystallize in the monoclinic space group P2(1)/n and show infinite chain structures. The coordination numbers of rare earth ions are nine.

INFRARED-SPECTRA OF DIMETHYLPHOSPHATE LANTHANIDE COMPLEXES

The infrared spectra of the crystalline solid samples of rare earth(III) dimethylphosphates Ln(DMP)3 (Ln = La, Ce, Nd) in the range 4000-100 cm-1 are discussed. It is shown that the spectra may be treated by dividing Ln(DMP)3 into two parts, an OP(OCH3)2O bridge and a LnO6 distortion octahedron. The absorption bands above 500 cm-1 may be clearly assigned. However, vibrational assignments in the far-infrared region are tentative.

THE CLEAVAGE REACTION OF THE MO-MO TRIPLE BOND - THE CRYSTAL-STRUCTURES OF MOLYBDENUM COMPLEXES [CPMO(CO)(2)(C(5)H(4)NS)], [CPMO(CO)(2)(C(9)H(6)NS)]O=PPH(3) AND [CPMO(CO)(2)(S(2)CNME(2)]

The reactions of [Cp2Mo2(CO)4] (1) with 2,2'-dipyridyl disulphide (C5H4NS-)2, 8,8'-diquinolyl disulphide (C9H6NS-)2 and tetramethyl thiuram disulphide (Me2NC(S)S-)2 in toluene solution resulted in the cleavage of the Mo-Mo triple bond to yield molybdenum complexes [CpMo(CO)2(C5H4NS)] (2), [CpMo(CO)2(C9H6NS)] (3) and [CpMo(CO)2(S2CNMe2)] (4), respectively. The molecular structures of 2, 3 . O=PPh3 and 4 were determined by X-ray diffraction studies. Crystals of 2 are monoclinic, space group P2(1)/n, with Z = 4, in a unit cell of dimensions a = 6.448(1), b = 12.616(2), c = 14.772(2) angstrom, beta = 92.85(1)-degrees. The structure was refined to R = 0.028 and R(w) = 0.039 for 1357 observed reflections. Crystals of 3 . O=PPh3 are triclinic, space group P1BAR, with Z = 2, in a unit cell of dimensions a = 11.351(3), b = 13.409(3), c = 9.895(2) angstrom, alpha = 94.59(2), beta = 90.35(2), gamma = 78.07(2)-degrees. The structure was refined to R = 0.033 and R(w) = 0.037 for 3260 observed reflections. Crystals of 4 are monoclinic, space group P2(1)/a and Z = 4 with a = 12.468(5), b = 7.637(2), c = 13.135(4) angstrom, beta = 96.62(3). The structure was refined to R = 0.032 and R(w) = 0.042 for 1698 observed reflections. Each of complexes 2-4 contains a cyclopentadienyl ligand, a cis pair of carbonyls and a chelate ligand (S,N donor or S,S donor). All the compounds have distorted square-pyramid structures.

SYNTHESIS AND CHARACTERIZATION OF HETEROPOLY BLUES OF BIS-2/17 MOLYBDOPHOSPHATE COMPLEXES WITH LANTHANIDE

Eight heteropoly blues of bis-2:17 molybdophosphate complexes with Lathanide, i.e., K17H2[Ln(P2Mo17O61)2] . nH2O and K17H4[Ln(P2Mo17O61)2] . nH2O were synthesized and characterized by elemental analyses potentiometric titration, IR, UV, polarography, cyclic voltammetry, X-ray photoelectron spectra X-ray powder diffraction, thermal analyses and ESR. Experimental results show that the properties of these series of heteropoly blues are different from those of their oxidized form, but no great changes in their structures were observed. The ligand P2Mo17O6110- remains alpha2-isomer's configuration.

X-RAY PHOTOELECTRON-SPECTRA OF SOME BIOINORGANIC COMPLEXES OF THE RARE-EARTHS WITH N-ACETYLALANINE

X-Ray photoelectron spectra of some bioinorganic complexes of La, Ce, PT, Nd, Sm and Eu with N-acetylalanine have been measured and the 3d5/2 and 3d3/2 main peaks and their satellites have also been assigned. ne spin-orbit splitting between the 3d5/2 and 3d3/2 core-level of the rare earth ion in these complexes becomes slightly larger than that of the free rare earth atom due to the effect of the crystal field. The satellite for the 3d main peaks of La in the solid state complex are in higher binding energy region and may be attributable to the L --> 4f charge-transfer shake-up process. The satellites for the 3d main peaks of Ce, Pr, Nd, Sm and Eu are in the lower binding energy region and may be attributable to the 4f --> L charge-transfer shake-down process.

PHOTOELECTRON-SPECTRA OF COMPLEXES OF NA AND LA WITH N-ACETYLALANINE AND N-ACETYLVALINE

X-ray photoelectron spectra of the bioinorganic complexes of Na and La with N-acetylalanine and N-acetylvaline have been measured. It has been found that the spectra of the O 1s core level in the complexes of Na with these amino acids are very different from those in the complexes of La with the same amino acids. The results indicate that in the complexes of La with N-acetylalanine and N-acetylvaline, both the oxygen atoms from the carboxyl group and the oxygen atoms from the carbonyl group of the amino acids will directly coordinate to the La ion, whereas only the oxygen atoms from the carboxyl group of the amino acids can directly coordinate to the Na ion in the complexes of Na with N-acetylalanine and N-acetylvaline.

THE SYNTHESES CHARACTERIZATION AND CRYSTAL-STRUCTURE OF RARE-EARTH COMPLEXES WITH L-PROLIN

The complexes of Ln(L-Pro)s(H2O)2(ClO4)3(Ln = Pr, Nd and Er. L-Pro = L-Proline) were synthesized and characterized by elemental analysis, IR. spectra and thermal analysis. The singal crystal Pr2(L-Pro)6(H2O)4(ClO4)6 Was also obtained. The crystal belongs to monoclinic, P2(1), a = 0.9879 (3) nm, b = 2.1883 (4) nm, c = 1.3393 (2)nm, beta = 91.23(2)-degrees, V = 2.895(1) nm3, Z = 2. R = 0.035 for 5032 observed reflections. The coordination polyhedron of Pr(III) ion comprises six oxygen atoms from L-Pro molecules and two water molecules. Each L-Pro molecule coordinates to two Pr(III) ions through its carboxyl group which serves as a bridging bidentate ligand to form onedimensional chain structure.

SYNTHESES, CHARACTERIZATION AND CRYSTAL-STRUCTURES OF THE COMPLEXES OF RARE-EARTH WITH M-METHYLBENZOIC ACID

REL3(RE=Y, La approximately Lu; HL = m-methylbenzoic acid) were synthesized, and their IR spectra were studied. The crystal structures of the complexes of neodymium and terbium were determined by X-ray diffraction method. Both of them crystallize in the monoclinic space group P2(1)/n and show infinite chain structures. The coordination numbers are nine (Nd3+) and eight (Tb3+), respectively.

STUDIES ON OLEFIN-COORDINATING TRANSITION-METAL CARBENE COMPLEXES .20. SYNTHESIS OF 1,3-CYCLOHEXADIENE(DICARBONYL) [ETHOXY(ARYL)-CARBENE]IRON COMPLEXES AND THEIR PHOSPHINE ADDUCTS - CRYSTAL-STRUCTURE OF C6H8(CO)2FEC(OC2H5)C6H4CH3-O

Reaction of 1,3-cyclohexadiene(tricarbonyl)iron (1) with ortho-substituted aryllithium reagents ArLi (Ar=o-CH3C6H4, o-CH3OC6H4, o-CF3C6H4) in ether at low temperature, and subsequent alkylation of the acylmetalates formed with Et3OBF4 in aqueous solution at 0-degrees-C or in CH2Cl2 at -60-degrees-C gave the 1,3-cyclohexadiene(dicarbonyl)[ethoxy(aryl)carbene]iron complexes (eta4-C6H8)(CO)2FeC(OC2H5)Ar (3, Ar = o-CH3C6H4; 4, Ar = o-CH3OC6H4), and the isomerized product (eta3-C6H8)(CO)2FeC(OC2H5)C6H4CF3-o (5), respectively, among which the structure of 3 has been established by an X-ray diffraction study. Complex 3 is monoclinic, space group P2(1) with a = 8.118(4), b = 7.367(4), c = 14.002(6) angstrom, beta = 104.09(3)-degrees, V = 812.2(6) angstrom3, Z = 2, D(c) = 1.39 g cm-3, R = 0.056, and R(w) = 0.062 for 976 observed reflections. Complexes 3 and 5 were converted into the chelated allyliron phosphine adducts(eta3-C6H8)(CO)2(PR31)FeC(OC2H5)Ar (6, Ar = o-CH3C6H4, R1 = Ph; 7, Ar = o-CH3C6H4, R1 = OPh; 9, Ar = o-CF3C6H4, R1 = Ph), by reaction with phosphines in petroleum ether at low temperatures.