Reaction of a ruthenium B-carboranyl hydride complex and BH3(SMe2): Selective formation of a pincer-supported metallaborane LRu(B3H8)

Reaction of a boryl hydride pincer complex (POBOP)Ru(H)(PPh₃) (POBOP?=?1,7-OP(i-Pr)₂-m-2-carboranyl) and BH₃(SMe₂) at 70?°C led to the selective formation of a pincer-supported metallaborane (POBOP)Ru(B₃H₈). Single crystal structure of (POBOP)Ru(B₃H₈) was determined. This complex features coordination of the carborane cluster through adjacent boryl and borane groups that impose significantly different trans-influence on the coordinated B₃H₈ fragment.     

Towards rod-shaped molecules based on the twelve-vertex ferratricarbollides

The compounds with a single and double -CH₂C₆H₄CH₂- spacer, [CpFeC₃B₈H₁₀-NH-CH₂C₆H₄CH₂-NH-C₃B₈H₁₀FeCp] and [CpFeC₃B₈H₁₀-N-(CH₂C₆H₄CH₂)₂-N-C₃B₈H₁₀FeCp], represent the first example of designed shaping by extremely stable cyclopentadienyl-ferratricarbollide (CpFeTCB) cages into rigid molecular constructions approaching linear arrangement.     

New approaches to cluster modification in the 12-vertex metallatricarbollide series

Cluster opening of [2-Cp-9-^tBuNH-closo-2,1,7,9-FeC₃B₈H₁₀] (1) , followed by oxidation, generates complexes [2-Cp-8-^tBuNH-closo-2,1,8,10-FeC₃B₈H₁₀] (2), [2-Cp-4-^tBuNH-closo-2,1,4,12-FeC₃B₈H₁₀] (3), [2-Cp-1-^tBuNH-closo-2,1,7,10-FeC₃B₈H₁₀] (4), and [1-Cp-10-^tBuNH-closo-1,2,3,10-FeC₃B₇H₉] (5). Another variation of the syntheses led to compounds [2-Cp-closo-2,1,8,10-FeC₃B₈H₁₁] (6), [4-Cp-1-^tBuNH-closo-4,1,6,8,-FeC₃B₉H₁₁] (7) and to two isomeric, not yet fully characterized, 13-vertex compounds of general nido structure [^tBuNH-Cp-FeC₃B₉H₁₂] (8 and 9).     

8-Dioxane ferra(III) bis(dicarbollide): A paramagnetic functional molecule as versatile building block for introduction of a Fe(III) centre into organic molecules

The synthesis of a new, paramagnetic closo-[(8-(-CH₂CH₂O)₂-1,2-C₂B₉H₁₀)(1′,2′-C₂B₉H₁₁)-3,3′-Fe]⁰ (3) is reported. This compound can serve as a versatile building block for construction of both anionic and zwitterionic derivatives, as exemplified by the synthesis of a series of compounds of general formula closo-[(8-X-(CH₂CH₂O)₂-1,2-C₂B₉H₁₀)(1′,2′-C₂B₉H₁₁)-3,3′-Fe], bearing organic end groups (X = NC₅H₅ (4), (C₆H₅)₃P (5), OH (6), and 2-O(1-CH₃O-C₆H₄) (7)) attached to the cluster by a diethyleneglycol spacer. Molecular structures of 3, 4, 5 and 7 were determined by single-crystal X-ray diffraction analysis and by the long-time neglected method of paramagnetic, high field NMR (¹H, ¹³C and ¹¹B) spectroscopy.     

Chemistry related to cluster-borane analogues of the cyclopentadienide anion and ferrocene: New developments

A review on cluster-borane analogues of the cyclopentadienide anion (Cp) and ferrocene is presented. Analogues of Cp that have been so far isolated and characterised are the 11-vertex triheteroboranes of general structure [nido-E₃B₈H₈]⁻ (where E = CH or P and their combinations), the molecules of which contain an open pentagonal face. These anions were used as effective ligands for the preparation of “half- and full-sandwich” complexes [CpFeE₃B₈H₈] and [Fe(E₃B₈H₈)₂], respectively - analogues of ferrocene. Developments in this area of cluster-borane chemistry that include recent results in the synthesis and Fe-complexation reactions of 11-vertex tricarbaboranes (tricarbollides), phosphadicarbollides, and diphosphacarbollides are the subject of this work.     

Metallacarborane chemistry of the hypho-[6,7-C2B6H13] anion: Reaction with nickelocene and the formation of three multimetallic nickel-boron clusters

The reaction of the hypho-[6,7-C₂B₆H₁₃]⁻ anion (1) with nickelocene and an excess of ‘proton sponge’ (1,8-bis-(dimethylamino-naphthalene)) in boiling acetonitrile leads to the formation of a pair of isomeric trimetallic nickel-boron clusters, [6,7,8-(CpNi)₃-1-CB₅H₆] (2) and [6,7,8-(CpNi)₃-2-CB₅H₆] (3), in a combined yield of 55%. Isomer (2) had been previously prepared from nido-2-CB₅H₉ but in much lower yield. Isomer (3) is without precedent and has been characterized using multi-nuclear NMR spectroscopy and mass spectrometry. Isomer (3) undergoes conversion to (2) via heating in boiling toluene. In addition to this isomeric pair, an interesting nido dimetallacarborane of constitution [6,6′-(CpNi)₂-7,7′-C₂B₆H₈] (4) has been isolated from the same reaction in 5% yield and characterized by single-crystal X-ray diffraction analysis.     

The enumeration of electron-rich and electron-poor polyhedral clusters

We present as dual processes the capping of closed triangulated polyhedra with apical atoms and the making of holes in such polyhedra either by puncture of the surface or by excision of atoms and their edges. These processes are shown to generate stable chemical species containing respectively less or more than 2n + 2 skeletal electrons. The former species are designated as electron-poor whereas the latter are called electron-rich. Pólya's enumeration method is used to enumerate the distinct ways of capping and excising the closed, triangulated polyhedra to yield systems containing from four to twelve vertices. For the enumeration of cappings the appropriate cycle index is that of the dual of the polyhedron being capped, whilst for the enumeration of the excisions the cycle index is that of the polyhedron being excised.     

Optimized Structures and Relative Stabilities of the Carboranes from Ab Initio Calculations

Ab initio calculations at the STO-3G level were performed on almost all of the possible isomers for the entire series of closo-carboranes, C₂B_n-2H_n, 5 ? n ? 12. Geometry optimizations using the gradient method were also included in all calculations. We report here the relative energies obtained for the various isomers as well as the optimized structures. These calculations confirm our previous predictions of relative stabilities obtained from topological charge stabilization. Comparisons of our structures with those from experimental data provide us with a measure of reliability for bond distances obtained using ab initio SCF MO calculations at the STO-3G level. Results from the geometry optimization substantiated the experimentally known fluxional behavior of the 8 and 11 atom polyhedra.     

两种不同晶形的邻羟基苯甲酸钬配合物的合成与晶体结构

合成了两种不同晶形的配合物，其组成分别为［Ｈｏ_２（ｏ－ＨＯＣ_６Ｈ_１ＣＯ_２）_６（Ｈ_２Ｏ）_４］·４Ｈ_２Ｏ及［Ｈｏ（ｏ－ＨＯＣ_６Ｈ４ＣＯ_２）_３·（Ｈ_２Ｏ）_２·２Ｈ_２Ｏ］_ｎ，用Ｘ射线衍射法测定了它们的结构：一种以二聚体形式存在，属三斜晶系（Ⅰ），其中钬离子的配位数为９；另一种呈无限链状聚合结构，属单斜晶系（Ⅱ），钬离子的配位数为８．同时还研究了它们的热分解过程．     

Syntheses and Crystal Structures of Pyrazoline Derivants

SNNHNH2 OSSNNHNH2 OS1 INTRODUCTION Pyrazoline derivatives, used as carrier transporting as well as emitting materials[1], have been widely investigated in many areas due to their blue light emission with high quantum yield[2～5], ready acces- sibility and easy processability. 1,3,5-Triaryl-2-pyrazo- lines are reported as the hole transporting or emitting Scheme 1N NN SEtOHmaterials in organic EL devices[6～8]. However, ben- zothiazoyl pyrazolinederivatives containing aro…     

Syntheses and Structures of Binaphthyl-bridged Schiff Bases

The reaction of dinaphthofuran with lithium in anhydrous diethyl ether led to a solution of the corresponding C,O-dilithiated intermediate which, upon treatment with DMF at ？78 oC, afforded, after hydrolysis, 2＇-hydroxy-1,1＇-binaphthyl-2-carbaldehyde in a good yield. Then binaphthyl-bridged Schiff bases were prepared by the condensation of 2＇-hydroxy-1,1＇-binaphthyl-2-carbaldehyde with the corresponding aromatic amines.     

Syntheses and Structures of Terminal Arylalumylene Complexes

Terminal arylalumylene complexes of platinum [Ar‐Al‐Pt(PCy₃)₂] (Ar=2,6‐[CH(SiMe₃)₂]₂C₆H₃ (Bbp) or 2,6‐[CH(SiMe₃)₂]₂‐4‐(tBu)C₆H₂ (Tbb)) have been synthesized either by the reaction of a dialumene–benzene adduct with [Pt(PCy₃)₂], or by the reduction of 1,2‐dibromodialumanes Ar(Br)Al‐Al(Br)Ar in the presence of [Pt(PCy₃)₂]. X‐Ray crystallographic analysis reveals that the Al? Pt bond lengths of these arylalumylene complexes are shorter than the previously reported shortest Al? Pt distance. DFT calculations suggest that the Al? Pt bonds in the arylalumylene complexes have a significantly high electrostatic character.     

Syntheses and Structures of Lanthanide Complexes with Isonicotinate

1 INTRODUCTION In recent years, chemists have paid their attention to the design and construction of extended metal- organic framework solids with potential applications, such as catalysts, nonlinear optical devices, ion ex- change, adsorption, sensors etc.[1, 2]. As one kind of polydentate ligands, isonicotinic acid has been exte- nsively employed to synthesize transition metal coo- rdination polymers[3, 4] with one-[5～8], two-[9～12] and three- dimensional[13～21] extended frameworks b…     

Syntheses and Structures of Xenon Trioxide Alkylnitrile Adducts

The potent oxidizer and highly shock‐sensitive binary noble‐gas oxide XeO₃ interacts with CH₃CN and CH₃CH₂CN to form O₃XeNCCH₃, O₃Xe(NCCH₃)₂, O₃XeNCCH₂CH₃, and O₃Xe(NCCH₂CH₃)₂. Their low‐temperature single‐crystal X‐ray structures show that the xenon atoms are consistently coordinated to three donor atoms, which results in pseudo‐octahedral environments around the xenon atoms. The adduct series provides the first examples of a neutral xenon oxide bound to nitrogen bases. Raman frequency shifts and Xe?N bond lengths are consistent with complex formation. Energy‐minimized gas‐phase geometries and vibrational frequencies were obtained for the model compounds O₃Xe(NCCH₃)_n (n=1–3) and O₃Xe(NCCH₃)_n?[O₃Xe(NCCH₃)₂]₂ (n=1, 2). Natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM), electron localization function (ELF), and molecular electrostatic potential surface (MEPS) analyses were carried out to further probe the nature of the bonding in these adducts.     

Syntheses and Crystal Structures of Functionalized Tetramethyl Resorcinarenes

Tetramethyl resorcinarene, which was obtained by acidic condensation of resorcinol with paraacetoaldehyde, was chemically modified to the functionalized O-acyl, O-tosyl and O-acetate derivatives by corresponding acylation, p-toluenesulfonylation and alkylation reactions. The single crystal structures of these functionalized resorcinarenes and the complex of tetramethyl resorcinarene with 2,2'-bipyridine were determined by X-ray diffraction method. All these resorcinarenes adopt the all-cis configuration with four methyl groups stretching to the down rim and form 1D or 2D structures through H-bonds.     

柱芳烃机械互锁结构的制备及功能化

柱芳烃是一类具有柱状空腔结构的大环主体,近年来逐渐成为主客体作用构筑超分子体系的重要模块之一。柱芳烃家族包含柱[5]芳烃到柱[15]芳烃等成员,其中柱[5]芳烃为热力学稳定产物,合成产率最高;其次为柱[6]芳烃。柱[5]芳烃或柱[6]芳烃可做为主体,参与构筑[1](准)轮烷、[1](准)索烃等机械自锁结构,以及[n]轮烷(n≥2)、[2]索烃、雏菊链等机械互锁结构;体系中独立分子之间存在相对运动,如轮烷中柱芳烃在轴线上可以进行穿梭运动;丰富的衍生基团赋予柱芳烃互锁结构相应的功能,如手性翻转、荧光共振能量转移、超分子凝胶、Langmuir膜、催化反应等,甚至基于柱芳烃轮烷还可构筑更复杂的树枝状分子。本文综述了柱芳烃超分子互锁体系的研究进展,详细阐述了基于柱芳烃的互锁结构的合成方法及其功能化并讨论了其在构筑分子器件及其他超分子复杂体系方面的应用前景。     

Syntheses and Molecular Structures of Liquid Pyrophoric Hydridosilanes

Trisilane, isotetrasilane, neopentasilane, and cyclohexasilane have been prepared in gram scale. In-situ cryo crystallization of these pyrophoric liquids in sealed capillaries on the diffractometer allows access to the single crystal structures of these compounds. Structural parameters are discussed and compared to gas-phase electron diffraction structures from literature and with the results from quantum chemical calculations. Significantly higher packing indices are found for the silanes compared to the corresponding alkanes. Radiation with ultraviolet light (365 nm) and parallel ESR (EPR) measurement shows that cyclohexasilane is easily split into radicals, which subsequently leads to the formation of branched and chain-like oligomers. The other compounds form no radicals under these conditions. NMR spectra of all four compounds have been recorded.