Formation of cobalt(iii) cations with semiquinonediimine ligands

The reactions of polynuclear cobalt(ii) trimethylacetates [Co(OH) _n (OOCCMe₃)_2–n ] _x , Co₆(₃-OH)₂(OOCCMe₃)₁₀(HOOCCMe₃)₄, or Co₄(₃-OH)₂(OOCCMe₃)₆(HOEt)₆ with an excess of N-phenyl-o-phenylenediamine (1) in toluene followed by treatment with atmospheric oxygen afforded the diamagnetic complex [Co{²-(NPh)(NH)C₆H₄}₂{¹-(NH₂)C₆H₄(NPhH)}]⁺(Me₃CCOO...H...OOCCMe₃)^– (3), whose cation contains the Co^III atom. The reaction of Co₄(₃-OH)₂(OOCCMe₃)₆(HOEt)₆ with a deficient amount of diamine 1 in acetonitrile under an argon atmosphere gave rise to the antiferromagnetic ionic complex [Co{²-(NPh)(NH)C₆H₄}₂MeCN]⁺[Co₂(₂,²-OOCCMe₃)(₂-OOCCMe₃)₂(²-OOCCMe₃)₂]^–·2MeCN (4), whose cation is an isoelectronic analog of the cation in complex 3. The structures of the new compounds were established by X-ray diffraction analysis.     

Synthesis and structure of new dinuclear palladium complex containing no bridging ligands

Oxidation of the mononuclear semiquinonediimine complex [(NPh)(NH)C₆H₄]₂Pd with silver trifluoromethanesulfonate afforded the diamagnetic dinuclear dicationic palladium complex {[(NPh)(NH)C₆H₄]₂Pd}₂(O₃SCF₃)₂ with a Pd...Pd distance of 3.267(1) . The complex was structurally characterized, and its spectroscopic and electrochemical properties were studied.     

Reactions of ortho-Phenylenediamine with a Nickel Trimethylacetate Complex

Interaction of ortho-phenylenediamine with the nonanuclear nickel trimethylacetate cluster Ni₉(₄-OH)₃(₃-OH)₃( _n -OOCMe₃)₁₂(HOOCCMe₃)₄(I) in an amine deficiency yields the antiferromagnetic trinuclear complex [Ni₃{-N,N"-(NH₂)₂C₆H₄}₂(HCCOOCMe₃)₃(₃-OH)(-OOCCMe₃)₄]⁺(OOCCMe₃)^–(III) containing bridging diamine ligands. Reaction of excess diamine with Ior IIIleads to the formation of the paramagnetic monomer Ni{²-o-(NH₂)₂C₆H₄}₂(OOCCMe₃)₂(IV), which reacts with atmospheric oxygen to form the known bis(semiquinonediimine) complex Ni[1,2-(NH)₂C₆H₄]₂(V).     

Strukturelle Abwandlungen an partiell silylierten Kohlenhydraten mittels Triphenylphosphan/Azodicarbonsäurediethylester, 4. Mitt.: Transformationen an Mannose und Galaktose

Reaction of methyl -D-galactopyranoside (1) with two equivalents oft-butyldimethylchlorosilane yields methyl 2,6-bis-O-(tBDMSi)--D-galactopyranoside (1 b), methyl 3,6-bis-O-(tBDMSi)--D-galactopyranoside (1 c) and methyl 4,6-bis-O-(tBDMSi)--D-galactopyranoside (1 d). Likewise methyl -D-mannopyranoside (6) affords methyl 2,6-bis-O-(tBDMSi)--D-mannopyranoside (6 d) and methyl 3,6-bis-O-(tBDMSi)--D-mannopyranoside (6 b), which can be isomerised withTPP/DEAD to methyl 4,6-bis-O-(tBDMSi)--D-mannopyranoside (6 f). Methyl 6-O-(tBDMSi)--D-galactopyranoside (1 a) and methyl 6-O-(tBDMSi)--D-mannopyranoside (6 a) can be prepared from1 or6 with one equivalent oft-butyldimethylchlorosilane.Without an external nucleophile the sugar derivatives1 a and1 b react withTPP/DEAD to form the 3,4-carbonato--D-galactopyranosides1 h and1 i and the 3,4-carbonato-2-O-ethoxycarbonyl--D-galactoside (1 j). In contrast to the formation of the compound1 i by means ofTPP/DEAD the reaction of1 a withTPP and Di-t-butyl-azodicarboxylate (DTBAD) yields the 2,3-anhydro--D-taloside (4 b) and only a small amount of1 i. The epoxide4 b can be cleaved withp-nitrobenzoylchloride/pyridine to the 3-chloro-3-deoxy-2,6-di-O-p-nitrobenzoyl--D-idoside (5). Reaction of1 c and1 d withTPP/DEAD yields the 2,3-anhydro--D-gulopyranoside (2), which can be transformed with NaN₃/NH₄Cl to the 2-azido-2-deoxy--D-idopyranoside (3).Likewise6 a and6 d can be converted to the 3,4-anhydro--D-talosides (7 a and7 b). Reaction of7 b or6 d withTPP/DEAD/NH₃ leads to 3,4-anhydro-2-azido-2-deoxy--D-galactopyranoside (8) and 3-azido-3-deoxy--D-altropyranoside (10), resp.The epoxide7 b is opened with NaN₃/NH₄Cl to the 4-azido-4-deoxymannosides (11 a and11 c) and the 3-azido-3-deoxy--D-idopyranoside (12), while the epoxide8 affords the 2,4-di-azido-2,4-dideoxy--D-glucopyranoside (9).Structures were elucidated by¹H-NMR-analysis of the corresponding acetates.

H. H. Brandstetter undE. Zbiral, Helv., im Druck.     

Dinuclear Ruthenium(II) Carbonyl Complexes Doubly Bridged by a Bromine Atom and a C5H3N-2-C(O)CH2-6-CH2 (Q) Group. Crystal Structures of Ru2(μ-Br)(μ-Q)Br(CO)4(PPh3)(MeOH) and Ru2(μ-Br)(μ-Q)Br(CO)3(PPh3)2

The oxidative addition reaction of 2,6-bis(bromomethyl)pyridine to Ru₃(CO)₁₂ gave scarcely soluble {Ru₂Br₂(-Q)(CO)₄} _n , 1, [Q=C₅H₃N-2-C(O)CH₂-6-CH₂] or a mixture of 1 and the mononuclear complex RuBr(Q)(CO)₃, 2, [Q=C₅H₃N-2-C(O)CH₂-6-CH₂Br] according to the reactant's mole ratio. Further reactions of 1 with some N- and P-donor ligands (L) afforded readily soluble dinuclear complexes, Ru₂(-Br)(-Q)Br(CO) _n (L) _m [n=4, m=1, L=PPh₃ 3a, or py 3b; n=3, m=2, L=PPh₃ 5a, or PPh₂(o-tolyl) 5b]. In this paper, the characterization of these products by the elemental analyses and the spectroscopic methods are described. The X-ray crystal structures of Ru₂(-Br) (-Q)Br(CO)₄(PPh₃)(MeOH), 4, which was obtained by crystallization of 3a from MeOH, and of 5a · (2CHCl ₃ ) are also described. Each of the metal atoms in 4 has a distorted octahedral coordination, while in 5a · (2CHCl ₃ ) one metal atom takes a distorted octahedral geometry and the other pseudooctahedral, which is completed by presenting a Ru ··· Br secondary bonding interaction.     

Cluster assisted formation of carbon-carbon bonds: Synthesis and crystal structures of two trinuclear heterometallic complexes CpWRu2(CO)7(μ-H)[OC(NMe2)CCHCHEt] and CpWRu2(CO)6(μ-H)[OC(NMe2)CCH(μ-η2-C6H4)]

Treatment of the carbamoyl cluster Ru₃(CO)₁₀(-H)(-²-OC(NMe₂)] with a two molar excess of CpW(CO)₃CCⁿ Pr in refluxing toluene produced a heterometallic cluster complex CpWRu₂(CO)₇(-H)[OC(NMe₂) CCHCHEt] (II), whereas the heterometallic clusters CpWRu₂(CO)₆(-H)[OC(NMe₂)CCH(-²-C₆H₃X)] (IVb, X=H;IVc, X=Me;IVd, X=F) were isolated from the reactions with CpW(CO)₃CCC₆H₄X under similar conditions. Both complexesII andIV were generated via a complicated sequence involving hydride migration to the acetylide, fragmentation of the cluster via removal of a Ru(CO)_n unit, coupling with the carbamoyl ligand and C-H bond activation at the substituent. Crystal data forII: space group R ;a=26.605(3),c=17.934(2) Å,Z=18; finalR _F =0.032,R _w =0.034 for 2720 reflections withI>2(I). Crystal data forIVb: space group C 2/c;a=16.120(6),b=14.972(2),c=18.872(4) Å, =95.46(2)°,Z=8; finalR _F =0.0375,R _w =0.0375 for 2074 reflections withI>3(I).     

Synthesis and Structural Studies of Group 2B Transition Metal Complexes with the Bulky Nitrogen Ligand Bis[<Emphasis Type="Italic">N</Emphasis>-(2,6-diisopropylphenyl) imino]acenaphthene

Summary. Group 2B transition metal complexes of bis[N-(2,6-diisopropylphenyl)imino]acenaphthene (o,o-iPr₂C₆H₃-BIAN), namely, [Hg(o,o-iPr₂C₆H₃-BIAN)Cl₂] (1), [Zn(o,o-iPr₂C₆H₃-BIAN)₂](ClO₄)₂ (2), and [Cd(o,o-iPr₂C₆H₃-BIAN)₂](ClO₄)₂ (3) have been synthesized and characterized. In complexes 2 and 3, IR, NMR, and conductivity measurements confirm the coordination of two (o,o-iPr₂C₆H₃-BIAN) ligands to the metal center with two discrete perchlorate anions. X-Ray crystal structure of 1 indicates a distorted tetrahedral geometry with two nitrogen atoms from (o,o-iPr₂C₆H₃-BIAN) ligand and two chloride atoms coordinating to the Hg(II) center.     

Kinetics and mechanism of the homogeneous reaction between some manganese(III)-Schiff base complexes and hydrogen peroxide in aqueous and sodium dodecyl sulphate solutions

Summary The kinetics of the reaction between H₂O₂ and some Schiff base complexes of Mn^III have been investigated in both aqueous and micellar sodium dodecyl sulphate (SDS) solution. The reaction rate is first order in both H₂O₂ and [complex], and inversely proportional to [H⁺]. The second-order rate constant increases in the sequence [Mn(salophen)(OAc)] > [Mn(salen)(OH₂)]-ClO₄ > [Mn(salen)(OAc)]H₂O, where salen = N,N-bis-(salicylidene)ethylenediamine and salophen = N,N-bis-(salicylidene)-o-phenylenediamine. At SDS concentrations below the critical micellar concentration, there is almost no effect on the rate of reaction whereas at higher concentrations the reaction rate increases slightly. A mechanism involving Mn^II and a peroxo intermediate is proposed.     

Synthesis and Crystal Structures of Copper(I) Complexes with N-Allylhexamethylenetetraminium Chloride Obtained in Different Acidic Media

The crystals of [(CH₂)₆N₄(C₃H₅)]Cu₂Cl₃ (I), [(CH₂)₆N₄(C₃H₅)]Cu₂Cl₃ (II), and [(CH₂)₆N₄(C₃H₅)]CuCl₂ (III) complexes were electrochemically synthesized (ac) from CuCl₂ · 2H₂O and N-allylhexamethylenetetraminium chloride in ethanol solutions at pH 6, 4.5, and 3. Their structures were determined using X-ray diffraction analysis (DARCh diffractometer, MoK radiation, /2 scan mode). Complex Icrystallizes in the monoclinic system: space group A2/a, a = 24.812(6) Å, b = 8.855(3) Å, c = 12.080(2) Å, = 89.21(3)°, and Z = 8. Complex II crystallizes in the triclinic system: space group P , a = 7.618(2) Å, b = 7.048(2) Å, c = 13.150(3) Å, = 97.50(2)°, = 92.70(2)°, = 100.74(2)°, and Z = 2. The crystals of complex III are orthorhombic: space group Pmn2₁, a = 7.478(2) Å, b = 8.827(2) Å, c = 9.662(3) Å, Z = 2. The organic cation in complex I acts as a tridentate ,,-ligand; that in complex II, as a bidentate ,-ligand. In complex III, the organic cation is involved in coordination with the copper(I) atom only through one nitrogen atom.     

Synthesis and Structure of Two Isomers of Re2Os2(CO)14(CNBu t )4: Clusters with Linear ReOs2Re Chains

The complexes (OC)₄(CNBu ^t )ReOs(CO)₃(CNBu ^t )Os(CO)₃(CNBu ^t )Re(CNBu ^t )(CO)₄ (A) and (OC)₃(CNBu ^t )₂ReOs(CO)₄Os(CO)₃(CNBu ^t )Re(CNBu ^t )(CO)₄ (B) have been isolated in low yield from the reaction of Os(CO)₃(CNBu ^t )₂ with Re₂(-H)(--C₂H₃)(CO)₈ in hexane at room temperature. Both compounds have approximately linear ReOs₂Re chains. The Re–Os lengths are in the range 2.9311(7)–2.952(1) Å the Os–Os lengths are 2.875(1) (A) and 2.8759(7) Å (B).     

Absorption spectra of 2-styryl-4-phenyl-thiazole ethiodides in organic solvents of varying polarities and determination of the formation constant of the charge transfer complex formed

The electronic absorption spectra of some 2-styryl-4-phenyl-thiazole ethiodides are studied in organic solvents of different polarities. The shorter wavelength band appearing in the visible region is assigned to an intramolecular charge transfer (CT)-transition originating from the phenyl moiety to the positively charged hetero ring, while the longer wavelength one is due to an intermolecular CT-transition from the iodide ion to the 2-styryl-4-phenyl-thiazolinium cation. These assignments are based on the nature of the aldehydic residue and effects of solvent, concentration, and temperature on both the position and absorptivity of the CT complex-band. It is concluded that the CT complex formed will be highly solvated inDMF, DMSO, ethanol and methanol relative to in CHCl₃, dioxane and acetone. The formation constant of the CT complex in solutions of different polarities is determined at different temperatures. Furthermore, the thermodynamic parameters H ^o, G ^o and S ^o for complex formation are calculated and discussed.

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Absorptionsspektren von 2-Styryl-4-phenyl-thiazol-ethiodiden in verschiedenen Lösungsmitteln und Bestimmung der Bildungskonstanten der Charge-Transfer-Komplexe

Zusammenfassung Die Elektronenanregungsspektren einiger substituierter 2-Styryl-4-phenyl-thiazol-ethiodide wurden in einigen Lösungsmitteln unterschiedlicher Polarität untersucht. Die Absorption bei kürzerer Wellenlänge wird einem intramolekularen Charge-Transfer (CT)-Übergang zugeordnet, die langwellige Bande einem intermolekularen CT-Übergang (Jodid—organ. Kation). Die Diskussion erfolgt basierend auf Substitutions-, Lösungsmittel-, Konzentrations-, und Temperatur-Effekten. Die Komplexbildungskonstanten und die thermodynamischen Parameter H ^o, G ^o und S ^o werden angegeben.

     

Magnetisch nichtäquivalente Methylenprotonen in einigen 2-substituierten 1,3-Benzodioxanen

Zusammenfassung Die magnetische Nichtäquivalenz der Methylenprotonen in 2-R-Benzo-1,3-dioxanen, mit R=C₆H₅,o-ClC₆H₄,m-ClC₆H₄,p-ClC₆H₄,o-BrC₆H₄,m-BrC₆H₄,p-BrC₆H₄,o-NO₂C₆H₄,m-NO₂C₆H₄,p-NO₂C₆H₄,o-CH₃OC₆H₄,m-CH₃OC₆H₄,p-CH₃OC₆H₄, -Naphthyl, -Naphthyl, -Thienyl und -Thienyl, wurde in (CD₃)₂CO, CDCl₃, CCl₄, CS₂ und C₆D₆ untersucht.

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Magnetic non equivalent methylenic protons of some 2-substituted 1.3-benzodioxanes

The magnetic non equivalence of the methylenic protons in 2-R-1.3-benzodioxanes, with R=C₆H₅,o-ClC₆H₄,m-ClC₆H₄,p-ClC₆H₄,o-BrC₆H₄,m-BrC₆H₄,p-BrC₆H₄,o-NO₂C₆H₄,m-NO₂C₆H₄,p-NO₂C₆H₄,o-CH₃OC₆H₄,m-CH₃OC₆H₄,p-CH₃OC₆H₄, -naphthyl, -naphthyl, -thienyl and -thienyl were studied in (CD₃)₂CO, CDCl₃, CCl₄, CS₂ and C₆D₆.

     

Synthesis and Structural Studies of Group 2B Transition Metal Complexes with the Bulky Nitrogen Ligand Bis[ N-(2,6-diisopropylphenyl) imino]acenaphthene

Group 2B transition metal complexes of bis[N-(2,6-diisopropylphenyl)imino]acenaphthene (o,o-iPr₂C₆H₃-BIAN), namely, [Hg(o,o-iPr₂C₆H₃-BIAN)Cl₂] (1), [Zn(o,o-iPr₂C₆H₃-BIAN)₂](ClO₄)₂ (2), and [Cd(o,o-iPr₂C₆H₃-BIAN)₂](ClO₄)₂ (3) have been synthesized and characterized. In complexes 2 and 3, IR, NMR, and conductivity measurements confirm the coordination of two (o,o-iPr₂C₆H₃-BIAN) ligands to the metal center with two discrete perchlorate anions. X-Ray crystal structure of 1 indicates a distorted tetrahedral geometry with two nitrogen atoms from (o,o-iPr₂C₆H₃-BIAN) ligand and two chloride atoms coordinating to the Hg(II) center.     

Synthesis of some 5′-O-amino acid derivatives of uridine as potential inhibitors ofUDP-glucuronosyltransferase

Summary In an attempt to develop potential inhibitors ofUDP-glucuronosyltransferase, some 5-O-amino acid derivatives of uridine were synthesized. N-protectedL-amino acids were coupled at the 5-O-position of 2,3-O-isopropylideneuridine by esterification employing the method of symmetrical anhydrides in presence of 4-dimethylaminopyridine, 5-O-(N-benzyloxycarbonyl-O-tert.butyl-L-threonl)-23-O-isopropylideneuridine (1), 5-O-(N-tert.butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylideneuridine and (2), 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (3), and 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (4) were obtained in good yield after column chromatography on silica gel. The treatment of2 withTFA/CH₂Cl₂ (6:1) at room temperature for 30 min led to a selective removal of theBoc group without deblocking of the 2,3-O-isopropylidene group of uridine. Treatment of2 withTFA/H₂O (5:1) at room temperature for 1 h, however, released bothBoc and 2,3-isopropylidene groups. TheZ group of1 was deprotected by catalytic hydrogenolysis over 10% Pd/C/ammonium formate.

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Synthese von 5-O-Aminosäurederivaten des Uridins als potentielle Inhibitoren derUDP-Glukuronosyl-Transferase

Zusammenfassung In einem Versuch, potentielle Inhibitoren derUDP-Glukuronosyl-Transferase zu entwickeln, wurden einige 5-O-Aminosäurederivate des Uridins synthetisiert. N-GeschützteL-Aminosäuren wurden durch Veresterung mit der 5-O-Position des 2,3-isopropylidenuridins gekuppelt (Methode der symmetrischen Anhydride in der Gegenwart von 5-Dimethylaminopyridin). Solcherweise wurden 5-O-(N-Benzyloxycarbonyl-O-tert.butyl-L-threonly)-2,3-O-isopropylidenuridin (1), 5-O-(N-tert.Butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylidenuridin (2), 5-O-(N-tert.Butyloxycarbonyl-L-leucyl)-2,3-O-isopropylidenuridin (3) und 5-O-(N-tert.Butyloxycarbonyl-L-valyl)-2,3-O-isopropylidenuridine (4) nach Säulenchromatographie (Kieselgel) in guter Ausbeute hergestellt. Die Behandlung von2 mitTFA/CH₂Cl₂ (6:1) bei Zimmertemperatur (30 min) führte zu einer selektiven Abspaltung derBoc-Gruppe ohne Deblockierung der 2,3-O-Isopropylidengruppe des Uridins. Eine Behandlung von2 mitTFA/H₂O (5:1) bei Zimmertemperatur für 1 Stunde führte hingegen zur Abspaltung sowohl derBoc als auch der 2,3-O-Isopropylidengruppe. DieZ-Gruppe von1 wurde durch katalytische Hydrogenolyse auf 10% Pd/C/Ammoniumformiat abgespalten.

     

The chemistry of cyclopentadienyl nitrosyl and related complexes of molybdenum,part 10(1). Cationic allyl complexes and attack thereon by nucleophiles

Summary The syntheses of [Mo(⁵-C₅H₅)(³-C₃H₄R)(CO)(NO)]⁺ (R=H, 1- or 2-Me) and [Mo(⁵-C₅H₅)(³-C₃H₅)(NCR)(NO)]⁺ (R=Me or Ph), by treatment of Mo(⁵-C₅H₅)(CO)₂(NO) with RC₃H₄Br and Ag⁺, and of Mo(⁵-C₅H₅)(³-C₃H₅)(NO)I with Ag⁺ in the presence of RCN, is described. Treatment of these cations with nucleophiles gives Mo(⁵-C₅H₅)(³-C₃H₅)(NO)X (X=halide, NCS or NCO), Mo(⁵-C₅H₅)(³-C₃H₅Q)(CO)(NO) (C₃H₅Q= propene ligand, Q= H, SCOMe, SEt, S₂CNMe₂, S₂CNEt₂, S₂CN(Bu-n)₂, C₅H₅, acac, OH, OMe or OAc), and [Mo(⁵-C₅H₅)(₂C₃H₅L)(CO)(NO)]⁺ (L=PEt₃, n-Bu₃P, PPh₃, PPh₂H, PMe₂Ph, C₅H₅N, 1-, 3- or 4-MeC₅H₄N and Me₂NNH₂). Reaction of [Mo(⁵-C₅H₅)(³-C₃H₅)(NCMe)(NO)⁺ with pyridine gave [Mo(⁵-C₅H₅)(³-C₃H₅)(pyr)(NO)]⁺, while treatment of [Mo(⁵-C₅H₅)(³-C₃H₅)(CO)(NO)]⁺ with PPh₃ in the presence of NaOEt afforded Mo(⁵-C₅H₅)(CO)(NO)(PPh₃). The¹H and¹³C n.m.r. spectra of these complexes are discussed particularly in relation to the occurrence ofexo andendo isomers of the allylic species. Comparison is made briefly between Mo(⁵-C₅H₅)(³-C₃H₅)(NO)I and Mo(C₅H₅)₂(NO)I.     

Palladium nitrosoarene complexes in reductive carbonylation of nitroarenes

The reactions of carbon monoxide with the palladium nitrosoarene complexes Pd₂(-OCOR)₂(—CH₂C₆H₄NO)₂ (1, R = Me, CF₃, Bu^t, or Ph) and Pd₂(-OCOR)₂(PhNC₆H₄NO)₂ (2, R = Me, CF₃, Bu^t, or Ph) were studied. Complexes 1 contain the o-nitrosotoluene molecule metallated at the methyl group. In complexes 2, the phenyl-o-nitrosophenylamide ligand coordinated via two nitrogen atoms can be considered as a nitrosobenzene derivative bearing the NPh group in the ortho position of the Ph ring. It all cases, carbonylation of the complexes afforded the corresponding aryl isocyanates Ar—N=C=O or the products of their further transformations. The mechanism of reductive carbonylation of nitroarenes catalyzed by palladium compounds and the role of palladium nitrosoarene complexes as possible intermediates in this process are discussed.     

Researches on crystal and molecular structures of nine-coordination mononuclear K[Eu III 2 (Edta)(H2O)3]·3.5H2O and binuclear K4[(HTtha)2]·13.5H2O

The crystal and molecular structures of the K[Eu^III(Edta)(H₂O)₃] 3.5H₂O (I) (H₄Edta = ethylenediaminetetraacetic acid) and K₄[Eu₂^III(HTtha)₂] 13.5H₂O (II) (H₆Ttha = triethylenetetraminehexaacetic acid) complexes have been determined by single-crystal X-ray diffraction analyses. The crystal of I belongs to orthorhombic crystal system and Fdd2 space group. The crystal data are as follows: a = 1.9849(6)nm, b = 3.5598(11)nm, c = 1.2222(4)nm, V = 8.636(5)nm³, Z = 16, M = 596.37, (calcd) = 1.835g/cm³, µ= 3.166mm^–1, and F (000) = 4752. The final R and wR values are 0.0269 and 0.0692 for 2936 (I > 2.0 (I)) reflections and 0.0317 and 0.0708 for all 7284 unique reflections, respectively. The [Eu^III(Edta)(H₂O)₃]^– complex anion has a nine-coordination pseudo-monocapped square antiprismatic structure in which the nine coordinated atom are two N and seven O atoms (four from one Edta ligand and three water molecules). The crystal of II belongs to monoclinic system and P2¹/n space group. The crystal data are as follows: a = 1.1337(3)nm, b = 2.5753(6)nm, c = 2.2138(6) nm, = 102.871(5)°, V = 6.301(3) nm³, Z = 4, M = 1682.33, (calcd) = 1.773g/cm³, = 2.339mm^–1, and F(000) = 3404. The final R and wR are 0.0514 and 0.0906 for 11144 (I> 2.0(I)) reflections and 0.0976 and 0.1068 for all 26 048 unique reflections, respectively. The whole complex molecule is composed of two close parts in which every one has a nine-coordination structure as a distorted monocapped square antiprism. The Ttha ligand in the [Eu ₂^III(HTtha)₂]^4– complex anion coordinates to one central Eu ³⁺ ion with three N atoms and four O atoms and to the other Eu³⁺ ion with two O atoms.From Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 901–909.Original English Text Copyright © 2004 by J. Wang, X. Zhang, Y. Zhang, Y. Wang, X. Liu, Z. Liu.This article was submitted by the authors in English.     

Complexation with diol host compounds. Part 1. Structures of the 1:2 molecular complexes oftrans-9, 10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene with acetophenone and with 3-methylcyclopentanone

The structures of the 1:2 molecular complexes of trans -9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene with acetophenone (1), (C₂₆H₂₀O₂·2 C₈H₈O) and with 3-methylcyclopentanone (2), (C₂₆H₂₀O₂·2C₆H₁₀O) have been determined by X-ray crystallography. The crystal data are as follows: Compound (1):P ,a =8.979(5) Å,b =9.316(3) Å,c = 11.12(1) Å, =94.40(6)°, = 106.53(6)°, = 109.92(5)°,V = 822.94 ų,Z = 1,R = 0.097 for 2549 unique reflections. Compound (2):P ,a = 8.958(7) Å,b =9.815(4) Å,c = 9.807(4) Å, = 96.88(3)°, = 109.21(8)°, = 103.33(7)°,V = 774.10 ų,Z = 1,R = 0.059 for 2494 unique reflections. The intermolecular arrangements in both structures are characterised by host-to-guest hydrogen bonding interactions. The thermal properties of compound (2) have been characterised by DTA and TGA thermograms.     

Synthesis and DFT calculations of oxido and phenylimido-rhenium(V) complexes incorporating the N,O donor ligand 2-[(2-hydroxyethylimino)methyl]phenol

The reactions of equimolar amounts of trans-[ReOC1₃(PPh₃)₂] or trans-[Re(NPh)(PPh₃)₂Cl₃] with a Schiff base formed by condensation of 2-hydroxy-4-methoxybenzaldehyde and ethanolamine (H₂L) result in the formation of cis-[ReO(HL)PPh₃Cl₂] (1a) and trans-[Re(NPh)(HL)(PPh₃)Cl₂] (2b), respectively, in good yields. 1a and 2b have been characterized by a range of spectroscopic and analytical techniques. The X-ray crystal structures of 1a and 2b reveal that 1a is an octahedral cis-Cl,Cl oxorhenium(V) complex, while 2b is a trans-Cl,Cl phenylimidorhenium(V) complex. The complexes are weakly emissive at room temperature with quantum yields of 10^?4. Density functional theory calculations of the electronic properties of the complexes were performed and are in agreement with the experimental results. The complexes display quasi-reversible Re(V)/Re(VI) redox couples in acetonitrile. There is reasonable agreement between the experimental and calculated redox potentials of 1a and 2b.     

Rare-Earth Substituted Polyoxoanions: [{La(CH3COO)(H2O)2(α2-P2W17O61)}2]16− and [{Nd(H2O)3(α2-P2W17O61)}2]14−

The lanthanum-substituted polyoxometalate [{La(CH₃COO)(H₂O)₂( ₂-P₂W₁₇O₆₁)}₂]^16– (1) and the neodymium-substituted species [{Nd(H₂O)₃( ₂ -P₂W₁₇O₆₁)}₂]^14– (2) have been synthesized and characterized by IR spectroscopy and elemental analysis. Single-crystal X-ray analysis was carried out on K₁₆[{La(CH₃COO)(H₂O)₂( ₂ -P₂W₁₇O₆₁)}₂]36H₂O, which crystallizes in the triclinic system, space group P¯1, with a=12.3863(6) Å, b=12.8934(6) Å, c=31.7285(14) Å, =84.2000(10)°, =81.2300(10)°, =61.6500(10)°, and Z=1; K_6.5Nd_2.5[{Nd(H₂O)₃( ₂-P₂W₁₇O₆₁)}₂]55H₂O, which crystallizes in the monoclinic system, space group P2 ₁ /n, with a=17.5030(9) Å, b=23.7842(12) Å, c=19.1869(10) Å, =100.6610(10)°, and Z=1. The head-on, trans-oid dimer 1 consists of two ( ₂ -P₂W₁₇O₆₁)^10– fragments connected by a lanthanum-acetate dimer, (La₂(CH₃COO)₂(H₂O)₄)⁴⁺. Each La³⁺ ion is nine-coordinated in a monocapped, square-antiprismatic fashion. The neodymium-derivative 2 is also a trans-oid dimer, but the mode of binding is different from 1 and is best described as side-on. Each Nd³⁺ ion is eight-coordinated in a square-antiprismatic fashion with three terminal water molecules.