Lanthanoid‐Based Ionic Liquids Incorporating the Dicyanonitrosomethanide Anion

A series of low‐melting‐point salts with hexakisdicyanonitrosomethanidolanthanoidate anions has been synthesised and characterised: (C₂mim)₃[Ln(dcnm)₆] ( 1 Ln ; 1 Ln = 1 La , 1 Ce , 1 Pr , 1 Nd ), (C₂C₁mim)₃[Pr(dcnm)₆] ( 2 Pr ), (C₄C₁pyr)₃[Ce(dcnm)₆] ( 3 Ce ), (N₁₁₁₄)₃[Ln(dcnm)₆] ( 4 Ln ; 4 Ln = 4 La , 4 Ce , 4 Pr , 4 Nd , 4 Sm , 4 Gd ), and (N_1112OH)₃[Ce(dcnm)₆] ( 5 Ce ) (C₂mim=1‐ethyl‐3‐methylimidazolium, C₂C₁mim=1‐ethyl‐2,3‐dimethylimidazolium, C₄C₁py=N‐butyl‐4‐methylpyridinium, N₁₁₁₄=butyltrimethylammonium, N_1112OH=2‐(hydroxyethyl)trimethylammonium=choline). X‐ray crystallography was used to determine the structures of complexes 1 La , 2 Pr , and 5 Ce , all of which contain [Ln(dcnm)₆]^3? ions. Complexes 1 Ln and 2 Pr were all ionic liquids (ILs), with complex 3 Ce melting at 38.1 °C, the lowest melting point of any known complex containing the [Ln(dcnm)₆]^3? trianion. The ammonium‐based cations proved to be less suitable for forming ILs, with complexes 4 Sm and 4 Gd being the only salts with the N₁₁₁₄ cation to have melting points below 100 °C. The choline‐containing complex 5 Ce did not melt up to 160 °C, with the increase in melting point possibly being due to extensive hydrogen bonding, which could be inferred from the crystal structure of the complex.     

稀土元素异硫氰酸盐二甲基亚砜配合物标准生成焓的测定

合成了通式为RE(NCS)_3·5DMSO的7种稀土元素异硫氰酸盐与二甲基亚砜的固态配合物(RE=La,Ce,Pr,Nd,Sm,Eu,Gd)。运用本文设计的热化学循环,采用量热法,测定了上述7种配合物在298.15K时的标准生成焓,并计算了它们的晶格能。     

Complexes of the Lighter Lanthanoid Nitrates with 15-crown-5 and 18-crown-6 ethers: Synthesis and characterization

Complexes of lanthanoid trinitrates Ln(NO₃)₃ with 15-crown-5 ether 1 (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd) and with 18-crown-6 ether 2 (Ln = La, Ce, Pr, Nd) having a 1:1 stoichiometry as well as 4:3 complexes with 2 (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd) have been synthesized and characterized. All the isolated complexes are solvent free. At 170–220° the 1:1 complexes of 2 are quantitatively transformed into 4:3 complexes. X-Ray powder diagrams of the neodymium complexes with 2 indicate that both the 1:1 and 4:3 complexes are genuine compounds. All the 1:1 complexes show a characteristic IR. absorption band at 875–880 cm^?1 absent from both the spectra of the free ligands and of the 4:3 complexes. The spectroscopic properties (IR. and electronic spectra, fluorescence lifetimes) of the complexes and the low magnetic moments of the Ln(III) ions in the complexes with Ln = Ce-Eu are indicative of a strong interaction between the lanthanoid ions and the crown ethers 1 and 2 .     

Lanthanide(III) Complexes of 4,10‐Bis(phosphonomethyl)‐1,4,7,10‐tetraazacyclododecane‐1,7‐diacetic acid (trans‐H6do2a2p) in Solution and in the Solid State: Structural Studies Along the Series

Complexes of 4,10‐bis(phosphonomethyl)‐1,4,7,10‐tetraazacyclododecane‐1,7‐diacetic acid (trans‐H₆do2a2p, H₆ L ) with transition metal and lanthanide(III) ions were investigated. The stability constant values of the divalent and trivalent metal‐ion complexes are between the corresponding values of H₄dota and H₈dotp complexes, as a consequence of the ligand basicity. The solid‐state structures of the ligand and of nine lanthanide(III) complexes were determined by X‐ray diffraction. All the complexes are present as twisted‐square‐antiprismatic isomers and their structures can be divided into two series. The first one involves nona‐coordinated complexes of the large lanthanide(III) ions (Ce, Nd, Sm) with a coordinated water molecule. In the series of Sm, Eu, Tb, Dy, Er, Yb, the complexes are octa‐coordinated only by the ligand donor atoms and their coordination cages are more irregular. The formation kinetics and the acid‐assisted dissociation of several Ln^III–H₆ L complexes were investigated at different temperatures and compared with analogous data for complexes of other dota‐like ligands. The [Ce( L )(H₂O)]^3? complex is the most kinetically inert among complexes of the investigated lanthanide(III) ions (Ce, Eu, Gd, Yb). Among mixed phosphonate–acetate dota analogues, kinetic inertness of the cerium(III) complexes is increased with a higher number of phosphonate arms in the ligand, whereas the opposite is true for europium(III) complexes. According to the ¹H NMR spectroscopic pseudo‐contact shifts for the Ce–Eu and Tb–Yb series, the solution structures of the complexes reflect the structures of the [Ce(H L )(H₂O)]^2? and [Yb(H L )]^2? anions, respectively, found in the solid state. However, these solution NMR spectroscopic studies showed that there is no unambiguous relation between ³¹P/¹H lanthanide‐induced shift (LIS) values and coordination of water in the complexes; the values rather express a relative position of the central ions between the N₄ and O₄ planes.     

Synthesis,spectroscopic characterization and thermal studies of some rare earth metal complexes of unsymmetrical tetradentate Schiff base ligand

The solid complexes of La(III), Ce(III), Pr(III), Nd(III), Sm(III) and Gd(III) with 4-hydroxy-3-(1-{2-(2-hydroxy-benzylidene)-aminophenylimino}-thyl)-6-methy-pyran-2-one (H₂L) derived from o-phenylenediamine, 3-acetyl-6-methyl-(2H)pyran,2,4(3H)-dione (dehydroacetic acid or DHA) and salicylic aldehyde have been synthesized and characterized by elemental analysis, conductometry, magnetic susceptibility, UV–visible, FTIR, ¹H NMR spectra, X-ray diffraction, and thermal analysis and screened for antimicrobial activity. The FTIR spectral data suggest that the ligand behaves as a dibasic tetradentate ligand with ONNO donar atoms sequence towards central metal ion. From the microanalytical data, the stoichiometry of the complexes has been found to be 1:1 (metal:ligand). The physico-chemical data suggest distorted octahedral geometry for La(III), Ce(III), Pr(III), Nd(III), Sm(III) and Gd(III) complexes. The X-ray diffraction data suggest monoclinic crystal system for La(III) and Ce(III) and orthorhombic crystal system for Pr(III) and Nd(III) complexes. Thermal behaviour (TGA/DTA) of the complexes was studied and kinetic parameters were determined by Horowitz–Metzger and Coats–Redfern methods. The ligand and their metal complexes were screened for antibacterial activity against Staphylococcus aureus, Escherichia coli and Bacillus sp. Fungicidal activity against Aspergillus niger, Trichoderma and Fusarium oxysporum.     

Coexistence of Two Thermally Induced Intramolecular Electron Transfer Processes in a Series of Metal Complexes [M(Cat‐N‐BQ)(Cat‐N‐SQ)]/[M(Cat‐N‐BQ)2] (M=Co,Fe, and Ni) bearing Non‐Innocent Catechol‐Based Ligands: A Combined Experimental and Theoretical Study

The different thermally induced intermolecular electron transfer (IET) processes that can take place in the series of complexes [M(Cat‐N‐BQ)(Cat‐N‐SQ)]/[M(Cat‐N‐BQ)₂], for which M=Co ( 2 ), Fe ( 3 ) and Ni( 4 ), and Cat‐N‐BQ and Cat‐N‐SQ denote the mononegative (Cat‐N‐BQ^?) or dinegative (Cat‐N‐SQ^2?) radical forms of the tridentate Schiff‐base ligand 3,5‐di‐tert‐butyl‐1,2‐quinone‐1‐(2‐hydroxy‐3,5‐di‐tert‐butylphenyl)imine, have been studied by variable‐temperature UV/Vis and NMR spectroscopies. Depending on the metal ion, rather different behaviors are observed. Complex 2 has been found to be one of the few examples so far reported to exhibit the coexistence of two thermally induced electron transfer processes, ligand‐to‐metal (IET^LM) and ligand‐to‐ligand (IET^LL). IET^LL was only found to take place in complex 3 , and no IET was observed for complex 4 . Such experimental studies have been combined with ab initio wavefunction‐based CASSCF/CASPT2 calculations. Such a strategy allows one to solicit selectively the speculated orbitals and to access the ground states and excited‐spin states, as well as charge‐transfer states giving additional information on the different IET processes.     

邻氯苯甲酸稀土配合物的合成、表征及结构

本文合成了邻氯苯甲酸与十五种稀土的配合物REL~3·H~2O(RE=Y,La～Lu,L=Clc~6H~4CO~2H),研究了它们的热分解及红外光谱.测定了钕、铽及镥三种稀土的配合物晶体结构,均属单斜晶系,空间群P2~1/n,稀土离子配位数为9,配合物呈无限链状聚合结构.     

The dinuclear scandium(III) cyclooctatetraenyl chloride complex di‐μ‐chlorido‐bis[(η8‐cyclooctatetraene)(tetrahydrofuran‐κO)scandium(III)]

Only a few cyclooctatetraene dianion (COT) π‐complexes of lanthanides have been crystallographically characterized. This first single‐crystal X‐ray diffraction characterization of a scandium(III) COT chloride complex, namely di‐μ‐chlorido‐bis[(η⁸‐cyclooctatetraene)(tetrahydrofuran‐κO )scandium(III)], [Sc₂(C₈H₈)₂Cl₂(C₄H₈O)₂] or [Sc(COT)Cl(THF)]₂ (THF is tetrahydrofuran), (1), reveals a dimeric molecular structure with symmetric chloride bridges [average Sc—Cl = 2.5972 (7) Å] and a η⁸‐bound COT ligand. The COT ring is planar, with an average C—C bond length of 1.399 (3) Å. The Sc—C bond lengths range from 2.417 (2) to 2.438 (2) Å [average 2.427 (2) Å]. Direct comparison of (1) with the known lanthanide (Ln) analogues (La, Ce, Pr, Nd, and Sm) illustrates the effect of metal‐ion (M ) size on molecular structure. Overall, the M —Cl, M —O, and M —C bond lengths in (1) are the shortest in the series. In addition, only one THF molecule completes the coordination environment of the small Sc^III ion, in contrast to the previously reported dinuclear Ln–COT–Cl complexes, which all have two bound THF molecules per metal atom.     

Investigation of properties of rare earth complexes with dibromo- p -methyl-methylsulfonazo by spectral correction technique

The reactions were sensitive between seven rare earth (RE) metals Nd(III), La(III), Ce(III), Pr(III), Sm(III), Eu(III) and Gd(III) and dibromo-p-methylmethylsulfonazo (DBMMSA) in acidic solution. The spectral correction method has been applied in the determination of properties of RE complexes instead of ordinary spectrophotometry. Composition ratios, real molar absorptivities (ε) and stepwise stability constants (K) of each of the RE complexes were determined easily because the method eliminated the absorption influence of excess of ligand on complex. Results showed that the cumulativeK values of the complexes were between 3.91 × 10¹⁴ and 2.34 × 10²⁸ and the real (not apparent) absorptivity between 8.85 × 10⁴ and 2.12 × 10⁵ l mol^-1cm^-1 at 640 nm.     

Reactions of Rare‐Earth Metal Based Lewis Pairs with Azides†

The reactivity of homoleptic rare‐earth metal aryloxide based Lewis pairs toward organic azide substrates has been investigated herein. Treatment of RE(OAr)₃ (RE = La, Sm, Y, and Sc, Ar = 2,6‐^tBu₂‐C₆H₃), PEt₃ and Me₃SiN₃ in 2 : 1 : 1 molar ratio resulted in formation of separated ion pair complexes [Me₃Si‐PEt₃]⁺[(ArO)₃RE‐N=N=N‐RE(OAr)₃]^– under mild conditions. Replacement of phosphine with the nitrogen‐containing Lewis base 1,4‐diazabicyclo[2.2.2]octane (DABCO) produced analogous rare‐earth azide complexes with [Me₃Si‐DABCO]⁺ counterions. In contrast, reaction of the La(OAr)₃/PEt₃ Lewis pair with 1‐adamantyl azide (AdN₃) afforded the typical frustrated Lewis pair‐type 1,1‐addition product. A tetrahydrofuran ring‐opening reaction was also observed for the resulting rare‐earth azide complex with the [Me₃Si‐PEt₃]⁺ cation, with cleavage of the C—O bond by Si/P cooperation.     

Structural Variations and Molecular Dynamics of Rare‐Earth Metal Complexes with the N,N‐Bis(2‐{pyrid‐2‐yl}ethyl)hydroxylaminato Ligand

The reaction of the donor‐functionalised N,N‐bis(2‐{pyrid‐2‐yl}ethyl)hydroxylamine and [LnCp₃] (Cp=cyclopentadiene) resulted in the formation of bis(cyclopentadienyl) hydroxylaminato rare‐earth metal complexes of the general constitution [Ln(C₅H₅)₂{ON(C₂H₄‐o‐Py)₂}] (Py= pyridyl) with Ln=Lu ( 1 ), Y ( 2 ), Ho ( 3 ), Sm ( 4 ), Nd ( 5 ), Pr ( 6 ), La ( 7 ). These compounds were characterised by elemental analysis, mass spectrometry, NMR spectroscopy (for compounds 1 , 2 , 4 and 7 ) and single‐crystal X‐ray diffraction experiments. The complexes exhibit three different aggregation modes and binding motifs in the solid state. The late rare‐earth metal atoms (Lu, Y, Ho and Sm) form monomeric complexes of the formula [Ln(C₅H₅)₂{η²‐ON(C₂H₄‐η¹‐o‐Py)(C₂H₄‐o‐Py)}] ( 1 – 4 , respectively), in which one of the pyridyl nitrogen donor atoms is bonded to the metal atom in addition to the side‐on coordinating hydroxylaminato unit. The larger Nd³⁺ and Pr³⁺ ions in 5 and 6 make the hydroxylaminato unit capable of dimerising through the oxygen atoms. This leads to the dimeric complexes [(Ln(C₅H₅)₂{μ‐η¹:η²‐ON(C₂H₄‐o‐Py)₂})₂] without metal–pyridine bonds. Compound 7 exhibits a dimeric coordination mode similar to the complexes 5 and 6 , but, in addition, two pyridyl functions coordinate to the lanthanum atoms leading to the [(La(C₅H₅)₂{ON(C₂H₄‐o‐Py)}{μ‐η¹:η²‐ON(C₂H₄‐η¹‐o‐Py)})₂] complex. The aggregation trend is directly related to the size of the metal ions. The complexes with coordinative pyridine–metal bonds show highly dynamic behaviour in solution. The two pyridine nitrogen atoms rapidly change their coordination to the metal atom at ambient temperature. Variable‐temperature (VT) NMR experiments showed that this dynamic exchange can be frozen on the NMR timescale.     

希土硝酸盐与胞嘧啶固体配合物的合成和性质研究

同过渡金属相比,对希土生物化学行为的研究不很充分。胞嘧啶是生命遗传的物质基础,与金属的作用有重要意义。已有人合成了过渡金属与胞嘧啶的配合物,并研究其配位方式。本文研究希土胞嘧啶配合物的合成及性质,这项工作尚未见文献报道。 一.配合物的合成     

Systematic Investigation of Reaction‐Time Dependence of Three Series of Copper–Lanthanide/Lanthanide Coordination Polymers: Syntheses,Structures, Photoluminescence,and Magnetism

Three series of copper–lanthanide/lanthanide coordination polymers (CPs) Ln^IIICu^IICu^I(bct)₃(H₂O)₂ [Ln=La ( 1 ), Ce ( 2 ), Pr ( 3 ), Nd ( 4 ), Sm ( 5 ), Eu ( 6 ), Gd ( 7 ), Tb ( 8 ), Dy ( 9 ), Er ( 10 ), Yb ( 11 ), and Lu ( 12 ), H₂bct=2,5‐bis(carboxymethylmercapto)‐1,3,4‐thiadiazole acid], Ln^IIICu^I(bct)₂ [Ln=Ce ( 2 a ), Pr ( 3 a ), Nd ( 4 a ), Sm ( 5 a ), Eu ( 6 a ), Gd ( 7 a ), Tb ( 8 a ), Dy ( 9 a ), Er ( 10 a ), Yb ( 11 a ), and Lu ( 12 a )], and Ln^III₂(bct)₃(H₂O)₅ [Ln=La ( 1 b ), Ce ( 2 b ), Pr ( 3 b ), Nd ( 4 b ), Sm ( 5 b ), Eu ( 6 b ), Gd ( 7 b ), Tb ( 8 b ), and Dy ( 9 b )] have been successfully constructed under hydrothermal conditions by modulating the reaction time. Structural characterization has revealed that CPs 1 – 12 possess a unique one‐dimensional (1D) strip‐shaped structure containing two types of double‐helical chains and a double‐helical channel. CPs 2 a – 12 a show a three‐dimensional (3D) framework formed by Cu^I linking two types of homochiral layers with double‐helical channels. CPs 1 b – 9 b exhibit a 3D framework with single‐helical channels. CPs 6 b and 8 b display visible red and green luminescence of the Eu^III and Tb^III ions, respectively, sensitized by the bct ligand, and microsecond‐level lifetimes. CP 8 b shows a rare magnetic transition between short‐range ferromagnetic ordering at 110 K and long‐range ferromagnetic ordering below 10 K. CPs 9 a and 9 b display field‐induced single‐chain magnet (SCM) and/or single‐molecule magnet (SMM) behaviors, with U_eff values of 51.7 and 36.5 K, respectively.     

Rare‐Earth Oxide Nanostructures: Rules of Rare‐Earth Nitrate Thermolysis in Octadecylamine

The decomposed regularity of rare‐earth nitrates in octadecylamine (ODA) is discussed. The experimental results show that these nitrates can be divided into four types. For rare‐earth nitrates with larger RE³⁺ ions (RE=rare earth, La, Pr, Nd, Sm, Eu, Gd), the decomposed products exhibited platelike nanostructures. For those with smaller RE³⁺ ions (RE=Y, Dy, Ho, Er, Tm, Yb), the decomposed products exhibited beltlike nanostructures. For terbium nitrate with a middle RE³⁺ ion, the decomposed product exhibited a rodlike nanostructure. The corresponding rare‐earth oxides, with the same morphologies as their precursors, could be obtained when these decomposed products were calcined. For cerium nitrate, which showed the greatest differences, flowerlike cerium oxide could be obtained directly from decomposition of the nitrate without further calcination. This regularity is explained on the basis of the lanthanide contraction. Owing to their differences in electron configuration, ionic radius, and crystal structure, such a nitrate family therefore shows different thermolysis properties. In addition, the potential application of these as‐obtained rare‐earth oxides as catalysts and luminescent materials was investigated. The advantages of this method for rare‐earth oxides includes simplicity, high yield, low cost, and ease of scale‐up, which are of great importance for their industrial applications.     

Cationic Allyl Complexes of the Rare‐Earth Metals: Synthesis,Structural Characterization,and 1,3‐Butadiene Polymerization Catalysis

Monocationic bis‐allyl complexes [Ln(η³‐C₃H₅)₂(thf)₃]⁺[B(C₆X₅)₄]^? (Ln=Y, La, Nd; X=H, F) and dicationic mono‐allyl complexes of yttrium and the early lanthanides [Ln(η³‐C₃H₅)(thf)₆]²⁺[BPh₄]₂^? (Ln=La, Nd) were prepared by protonolysis of the tris‐allyl complexes [Ln(η³‐C₃H₅)₃(diox)] (Ln=Y, La, Ce, Pr, Nd, Sm; diox=1,4‐dioxane) isolated as a 1,4‐dioxane‐bridged dimer (Ln=Ce) or THF adducts [Ln(η³‐C₃H₅)₃(thf)₂] (Ln=Ce, Pr). Allyl abstraction from the neutral tris‐allyl complex by a Lewis acid, ER₃ (Al(CH₂SiMe₃)₃, BPh₃) gave the ion pair [Ln(η³‐C₃H₅)₂(thf)₃]⁺[ER₃(η¹‐CH₂CH?CH₂)]^? (Ln=Y, La; ER₃=Al(CH₂SiMe₃)₃, BPh₃). Benzophenone inserts into the La? C_allyl bond of [La(η³‐C₃H₅)₂(thf)₃]⁺[BPh₄]^? to form the alkoxy complex [La{OCPh₂(CH₂CH?CH₂)}₂(thf)₃]⁺[BPh₄]^?. The monocationic half‐sandwich complexes [Ln(η⁵‐C₅Me₄SiMe₃)(η³‐C₃H₅)(thf)₂]⁺[B(C₆X₅)₄]^? (Ln=Y, La; X=H, F) were synthesized from the neutral precursors [Ln(η⁵‐C₅Me₄SiMe₃)(η³‐C₃H₅)₂(thf)] by protonolysis. For 1,3‐butadiene polymerization catalysis, the yttrium‐based systems were more active than the corresponding lanthanum or neodymium homologues, giving polybutadiene with approximately 90 % 1,4‐cis stereoselectivity.     

NMR‐based analysis of structure of heteroleptic triple‐decker (phthalocyaninato) (porphyrinato) lanthanides in solutions

A novel approach for the structural analysis of heteroleptic triple‐decker (porphyrinato)(phthalocyaninato) lanthanides(III) in solutions is developed. The developed approach consists in molecular mechanics (MM+) optimization of the geometry of the complex taking into account the lanthanide‐induced shift (LIS) datasets. LISs of the resonance peaks in ¹H NMR spectra of a series of symmetric complexes [An₄P]Ln[(15C5)₄Pc]Ln[An₄P], where An₄P^2? is 5,10,15,20‐tetrakis(4‐methoxyphenyl)porphyrinato‐dianion, [(15C5)₄Pc]^2? is 2,3,9,10,16,17,24,25‐tetrakis(15‐crown‐5)phthalocyaninato‐dianion and Ln = La, Ce, Pr, Nd, Sm, Eu, are analyzed. Analysis of LISs showed two sets of protons in the molecule with opposite signs of shift. Two‐nuclei analysis of LISs testifies isostructurality of the whole series of investigated complexes in solution despite contraction of the lanthanide ions. Model‐free separation of contact and dipolar contributions of LISs was performed with one‐nucleus technique and did not show changes in contact and dipolar terms within the investigated series. MM+ optimization of the molecular structure allowed the interpretation of features of LIS for each particular group of protons. Parameterization of MM + ‐optimized model of molecule with values of structure‐dependent dipolar contributions of LIS allows the development of the precise structural model of the triple‐decker complex in solution. This approach allows the determination of the geometry and structure of the sandwich macrocyclic tetrapyrrolic complexes together with conformational analysis of flexible peripheral substituents in solutions. The developed method can be applied with minor modifications for the determination of structural parameters of other types of lanthanides(III) complexes with tetrapyrrolic ligands and also supramolecular systems based on them. Copyright © 2010 John Wiley & Sons, Ltd.     

The Features of Interaction of Bis(4, 6‐di‐tert‐butyl‐N‐(2, 6‐diisopropylphenyl)‐o‐amidophenolato)tin(IV) with Bromine and Iodine

The oxidation of tin(IV) bis‐amidophenolate (APiPr)₂Sn · THF ( I ) by bromine and iodine leads to the formation of monoradical mixed‐ligand complexes (APiPr)(ISQiPr)SnBr · THF ( II ) and (APiPr)(ISQiPr)SnI · THF ( III ) or diradical complexes (ISQiPr)₂SnBr₂ ( IV ) and (ISQiPr)₂SnI₂ ( V ), respectively [APiPr = dianion 4, 6‐di‐tert‐butyl‐N‐(2, 6‐diisopropylphenyl)‐o‐amidophenolate; ISQiPr = radical‐anion 4, 6‐di‐tert‐butyl‐N‐(2, 6‐diisopropylphenyl)‐o‐iminobenzosemiquinone], depending on the molar ratio of reagents (2:1 or 1:1). According to EPR data for compounds II and III , the unpaired electron is delocalized between both organic ligands. The EPR spectrum of IV in toluene matrix at 130 K is typical for diradical species with S = 1 with parameters D = 530 G, E = 105 G. The mixed‐ligand complexes II and III are unstable and undergo to symmetrization leading to formation of IV or V . The molecular structures of IV and V are determined by X‐ray analysis.     

Über die aldehydselektivität von alkylkomplexen von scandium,yttrium, lanthan und lanthaniden aldehyd/keton-konkurrenzversuchen

In-situ prepared alkyl complexes Hal₂M-Alk (Alk = Me, Bu) of the f-metals Ce, Pr, Nd, Sm, Gd exhibit very low selectivity in competition experiments between heptanal and diethylketone in THF, whereas the selectivity of complexes Hal₂M-Me (M = Sc, Y, La) is distinctly higher with decreasing tendency in the sequence Sc>Y>La. These and previously reported¹ results led to a general working hypothesis about the reasons of the aldehyde-selectivity of transition metal alkyls.     

RE(III)与2-羰基丙酸水杨酰腙配合物的合成、表征及热化学

用2-羰基丙酸水杨酰腙与轻稀土硝酸盐反应, 合成了7种新的配合物. 经元素分析、化学分析及X射线粉末衍射等手段确定了其组成为RE(C10H9N2O4)(C10H8N2O4)•nH2O(RE＝La、Ce、Pr、Nd、Sm、Eu、Gd), 用红外、紫外、荧光光谱分析对以上配合物的结构进行了表征; 用微热量计测定了稀土芳酰腙配合物的溶解焓, 发现其溶解焓数据不随稀土原子序数单调变化, 而呈转折变化, 可认为呈稀土的四分组现象的前两组.     

Rare-earth metal allyl and hydrido complexes supported by an (NNNN)-type macrocyclic ligand: synthesis, structure, and reactivity toward biomass-derived furanics

The preparation and characterization of a series of neutral rare‐earth metal complexes [Ln(Me₃TACD)(η³‐C₃H₅)₂] (Ln=Y, La, Ce, Pr, Nd, Sm) supported by the 1,4,7‐trimethyl‐1,4,7,10‐tetraazacyclododecane anion (Me₃TACD^?) are reported. Upon treatment of the neutral allyl complexes [Ln(Me₃TACD)(η³‐C₃H₅)₂] with Brønsted acids, monocationic allyl complexes [Ln(Me₃TACD)(η³‐C₃H₅)(thf)₂][B(C₆X₅)₄] (Ln=La, Ce, Nd, X=H, F) were isolated and characterized. Hydrogenolysis gave the hydride complexes [Ln(Me₃TACD)H₂]_n (Ln=Y, n=3; La, n=4; Sm). X‐ray crystallography showed the lanthanum hydride to be tetranuclear. Reactivity studies of [Ln(Me₃TACD)R₂]_n (R=η³‐C₃H₅, n=0; R=H, n=3,4) towards furan derivatives includes hydrosilylation and deoxygenation under ring‐opening conditions.