Alkali Metal and Trimethylsilyl Carbamoselenothioates – Synthesis,Structure, and some Reactions

This paper describes the synthesis and some reactions of potassium, rubidium, cesium and trimethylsilyl carbamoselenothioates. The potassium salts were synthesized in 70–80 % yields by reacting the corresponding thiocarbamoyl chlorides with potassium selenide in acetonitrile. Furthermore, the rubidium and cesium salts were obtained in good yields by treating the trimethylsilyl esters with the corresponding metal fluorides. The crystal structure of acetonitrile‐solvated potassium N,N‐dimethylcarbamoselenothioate consisted of dimeric units, featuring μ‐carbamoselenothioate anions associated with potassium cations that are located on the upper and lower sides of a plane involving two opposing carbamoselenothioate groups. These heavier alkali metal salts readily reacted with alkyl halides to give both S‐ and Se‐alkyl esters. The reaction of the potassium salts with trimethylsilyl chlorides forms S‐ and Se‐trimethylsilyl carbamoselenothioates which are in equilibrium. The reaction of the salts and silyl esters with organo Group‐14 and ‐15 elements halides gave exclusively the corresponding Se‐substituted products in good yields.     

O‐Triorganosilyl Carbamoselenoates – Synthesis and Reactions

A series of O‐triorganosilyl carbamoselenoates were isolated in good yields from the reaction of sodium or potassium carbamoselenoates with triorganosilyl chlorides. The O‐silyl carbamoselenoates readily reacted with RbF and CsF and with organo‐germanium, ‐tin, and ‐lead halides and gave the corresponding heavy alkali metal and Se‐substituted Group 14 organometal and carbamoselenoates in moderate to good yields.     

在碱金属/液氨作用下两类还原反应的机理探讨

碱金属/液氨溶液具有很强还原性,在有机合成中有着广泛的运用。在高等教育出版社出版的由邢其毅、裴伟伟、徐瑞秋以及裴坚等人编著的《基础有机化学》(第3版)中描述了在碱金属/液氨作用条件下的两类还原反应:炔烃被还原为烯烃的反应和Birch还原反应。一般认为这两种反应均生成了自由基负离子中间体。本文结合近几年的文献报道,对它们的机理进行进一步的探讨。     

铟（Ⅲ）的碱金属卤化物与冠醚配合物的合成及表征

在萃取研究过程中,合成了10种由四溴(或碘)合铟(Ⅲ)配阴离子与苯并-15-冠-5或二苯并-18-冠-6合钾(或钠)配阳离子相结合所形成的新型固体配合物。经元素分析、红外光谱及差热-热重等方法对配合物进行了表征。通过与相应的冠醚碱金属苦味酸盐配合物结构性质的对比,较合理地解释了这两类萃取体系之间存在的某些差别。     

Alkali Metal Compounds of Hydroquinone: Synthesis and Crystal Structure

A number of novel routes to the alkali metal compounds of hydroquinone M₂[p‐C₆H₄O₂] (M = Li, Na, K, Rb, Cs) and M[p‐C₆H₄O(OH)] (M = K, Rb, Cs) have been synthetically explored. The selective synthesis of the alkali 4‐hydroxyphenolates and 1, 4‐phenylenediolates is based on optimized reaction conditions (solvents, temperatures). All compounds were structurally characterized by means of powder X‐ray diffraction using Rietveld profile refinement including C—C and C—O bond distance restraints. The atomic arrangement of M₂[p‐C₆H₄O₂](M = Na, K) (tetragonal, space group: P4₂/ncm) is characterized by infinite pillars of [M₂^[3]O₂^[3]]‐units along the c axis connected by [p‐C₆H₄O₂]^2—‐anions with stacking direction along c. The coordinatively unsaturated alkali metals, surrounded by three oxygen atoms, exhibit symmetrical (K) as well as asymmetrical (Na) interactions with the phenylene rings. M[p‐C₆H₄O(OH] (M = K, Rb) (tetragonal, space group: P4/n) forms hydrogen‐bridged linear chains of [p‐C₆H₄O(OH)]^—‐anions along the c direction. The phenylene planes of neighboring chains have an almost orthogonal arrangement while the interchain planes are parallel. K and Rb are fourfold coordinated by two different oxygen coordination spheres.     

Alkali Metal and Organo Group‐14 Element Ferrocenecarbo­selenoates: Synthesis and Structures

Lithium, sodium, and potassium ferrocenecarboselenoates were synthesized in good yields by the reaction of ferrocenoyl chloride with the corresponding metal selenides. In air, the saltsquickly oxidized to give diferrocenoyl diselenide. The salts readily reacted with alkyl and organo‐germanium, ‐tin and ‐lead halides to give the corresponding Se‐alkyl and Se‐organo Group‐14 element ferrocenecarboselenoates [(FcCOSe)_xMPh_4–x (M = Ge, Sn, Pb; x = 1–3) in moderate to good yields. In contrast, the reaction of the sodium and potassium salts with trimethylsilyl chloride led to O‐trimethylsilyl ferrocenecarboselenoate FcCSeOSiMe₃. Treatment of the O‐silyl ester with RbF and CsF led to rubidium and cesium ferrocenecarboselenoates, respectively, in good yields. The structures of FcCOSetBu, (FcCOSe)₂SnPh₂, and FcCOSePbPh₃ were revealed by X‐ray molecular structure analysis.     

Compounds of Alkali Metal Anions

Anions of sodium, potassium, rubidium, and cesium are stable both in suitable solvents and in crystalline solids. The latter can be prepared either by cooling a saturated solution or by rapid solvent evaporation. Thermodynamic arguments show that alkali metal anions can probably exist in saturated solutions of the alkali metals in any compatible solvent, but that below saturation, dissociation into the cation and solvated electrons is favored in highly polar solvents such as ammonia. The key to solvent-free salts of the alkali metal anions is stabilization of the cation by incorporation into a suitable crown or cryptand complex. By using such complexes it also appears possible to produce “electride” salts in which the charge of the complexed cation is balanced by a trapped electron. The chemical, electrical, and optical properties of salts of the alkali metal anions and “electrides” could provide useful applications.     

气相中碱金属离子与丝氨酸、亮氨酸和赖氨酸五肽复合物的裂解反应简

为了探索金属离子对含有不同侧链的多肽气相解离的影响,采用质谱法研究了碱金属离子Li+,Na+,K+,Rb+和Cs+分别与丝氨酸、亮氨酸和赖氨酸五肽(分别简写为S5,L5和K5)形成的复合物的裂解反应. 质谱定性结果表明,5种碱金属离子均可以在气相中与丝氨酸、亮氨酸和赖氨酸五肽形成配合比为1：1 和2：1的非共价复合物;竞争反应结果表明,随着碱金属离子半径的增加,它们与3种五肽的结合能力逐渐减弱. 质谱定量结果表明,K+与丝氨酸、亮氨酸和赖氨酸五肽复合物的结合常数分别为8.94×104,2.83×104和2.50×103 L/mol,表明K+与五肽复合物的结合强度按照丝氨酸、亮氨酸和赖氨酸的顺序依次减小. 含不同侧链碱金属离子-五肽复合物的碰撞诱导解离结果表明,复合物的碎裂主要发生在骨架上,丝氨酸五肽复合物最易碎裂,亮氨酸五肽复合物其次,赖氨酸五肽复合物则较难碎裂,且3种复合物的侧链断裂情况也呈现明显差异. 此外,研究了Na+与亮氨酸五肽复合物所产生的碎片离子,分析了不同离子之间的来源关系,并以Dunbar的复合物理论模型为依据,推测在碎裂过程中,碱金属离子可能向五肽的碳端或氮端偏移. 质谱碎片分析结果表明,在2：1的非共价复合物中,第一个碱金属离子与五肽上4个酰胺键的羰基结合,第二个碱金属离子与五肽的羧基氧原子结合.     

气相中碱金属离子与丝氨酸、 亮氨酸和赖氨酸五肽复合物的裂解反应

为了探索金属离子对含有不同侧链的多肽气相解离的影响, 采用质谱法研究了碱金属离子Li⁺, Na⁺, K⁺, Rb⁺和Cs⁺分别与丝氨酸、 亮氨酸和赖氨酸五肽(分别简写为S5, L5和K5)形成的复合物的裂解反应. 质谱定性结果表明, 5种碱金属离子均可以在气相中与丝氨酸、 亮氨酸和赖氨酸五肽形成配合比为1∶1 和2∶1的非共价复合物; 竞争反应结果表明, 随着碱金属离子半径的增加, 它们与3种五肽的结合能力逐渐减弱. 质谱定量结果表明, K⁺与丝氨酸、 亮氨酸和赖氨酸五肽复合物的结合常数分别为8.94×10⁴, 2.83×10⁴和2.50×10³ L/mol, 表明K⁺与五肽复合物的结合强度按照丝氨酸、 亮氨酸和赖氨酸的顺序依次减小. 含不同侧链碱金属离子-五肽复合物的碰撞诱导解离结果表明, 复合物的碎裂主要发生在骨架上, 丝氨酸五肽复合物最易碎裂, 亮氨酸五肽复合物其次, 赖氨酸五肽复合物则较难碎裂, 且3种复合物的侧链断裂情况也呈现明显差异. 此外, 研究了Na⁺与亮氨酸五肽复合物所产生的碎片离子, 分析了不同离子之间的来源关系, 并以Dunbar的复合物理论模型为依据, 推测在碎裂过程中, 碱金属离子可能向五肽的碳端或氮端偏移. 质谱碎片分析结果表明, 在2∶1的非共价复合物中, 第一个碱金属离子与五肽上4个酰胺键的羰基结合, 第二个碱金属离子与五肽的羧基氧原子结合.     

肌醇在碱金属氯化物溶液中的体积性质

使用精密数字密度计测定了298.15和308.15 K肌醇在不同浓度的LiCl-H2O、NaCl-H2O或KCl-H2O溶液中的密度, 计算了肌醇的表观摩尔体积Vφ和极限偏摩尔体积Vθφ , 得到了其由纯水溶剂转移至混合溶剂中的迁移偏摩尔体积⊿trsVθ椎 .结果表明, LiCl, NaCl和KCl在溶液中对肌醇的体积性质影响显著, 极限偏摩尔体积Vθφ和极限迁移偏摩尔体积⊿trsVθφ都随盐浓度的增大而增加;温度对肌醇的极限偏摩尔体积和极限迁移偏摩尔体积只有轻微影响. 从分子-离子间的相互作用角度对实验结果进行了讨论.     

Alkali Metal-Transition Metal π-Complexes

In this progress report a new principle is described for the synthesis of multimetal π-complexes with hitherto unknown structural features. The nickel(0)-olefin complexes 1,5,9-cyclododecatrienenickel(0) and bis(1,5-cyclooctadiene)nickel(0) react unexpectedly with main-group metals, in particular alkali metals, their hydrides, and organometallic compounds, to give nickelligand species with a surplus charge. These species endeavor to transfer the excess charge onto π-ligands such as olefins or dinitrogen. Multimetal complexes with electron rich transition metal π-ligand units can, in addition, be prepared from metallocenes, alkali metals, and unsaturated compounds. The syntheses, structures, and reactions of this new class of substances will be summarized.     

Advanced Current Collectors for Alkali Metal Anodes

High-energy-density batteries are in urgent need to solve the ever-increasing energy storage demand for portable electronic devices, electric vehicles, and renewable solar and wind energy systems. Alkali metals, typically lithium(Li), sodium(Na) and potassium(K), are considered as the promising anode materials owing to their low electrochemical potential, low density, and high theoretical gravimetric capacities. However, the problem of dendrite growth of alkali metals during their plating/stripping process will lead to low Coulombic efficiencies, a short lifespan and huge volume expansion, eventually hindering their practical commercialization. To resolve this issue, a very effective approach is engineering the anodes on structured current collectors. This review summarizes the development of the alkali metal batteries and discusses the recent advances in rational design of anode current collectors. First, the challenges and strategies of suppressing alkali-metal dendrite growth are presented. Then the special attention is paid to the novel current collector design for dendrite-free alkali metal anodes. Finally, we give conclusions and perspective on the current challenges and future research directions toward advanced anode current collectors for alkali metal batteries.     

Synthesis and Crystal Structures of Alkali and Alkaline Earth Metal Complexes of 3,5-Dinitropyrazolyl-4-carboxylate

The synthesis and crystal structures of 3,5-dinitro-1H-pyrazolyl-4-carboxylic acid (H₂dnpzc) and its four complexes with Ca²⁺, Ba²⁺, Na⁺ and K⁺ are reported in this paper. Ca(dnpzc) · 5H₂O exhibits a 1D polymeric structure, whereas Ba(dnpzc) · 4H₂O possesses a 2D structure. The structure of Na₂(dnpzc) · 4H₂O consists of 2D layers of [Na(dnpzc)]^–_n and 1D chains of [Na(H₂O)₃]⁺_n. K₂(dnpzc) · H₂O has a true 3D structure. It was observed that the doubly deprotonated ligand (dnpzc^2–) can act as a versatile bridge to form polymeric structures by varying combinations of its 8 potential donor atoms (two carboxy O atoms, two pyrazolyl N atoms and four nitro O atoms). Particularly in the structure of K₂(dnpzc) · H₂O, all the 8 donor atoms of dnpzc^2– take part in the coordination and as many as 10 potassium atoms are connected by one ligand.     

DFT Study of Alkali Metal Atom Adsorption on Defect-Free MgO(001) Surface

The adsorption of isolated alkali metal atoms (Li, Na, K, Rb, and Cs) on defect-free sur-face of MgO(001) has been systemically investigated with density functional theory using a pseudopotential plane-wave approach. The adsorption energy calculated is about -0.72 eV for the lithium on top of the surface O site and about one third of this value for the other alkali metals. The relatively strong interaction of Li with the surface O can be explained by a more covalent bonding involved, evidenced by results of both the projected density of states and the charge density difference. The bonding mechanism is discussed in detail for all alkali metals.     

Synthesis and Structural Characterization of Alkali Metal Guanidinates

Reactions of 1,3-diisopropylcarbodiimide with alkali metal amides, MN（SiMe3）2 （M=Li or Na） in hexane or THF produced the alkali metal guanidinates { （i-PrN）2C [N（SiMe3）2]Li }2 （1） and { （i-PrN）2C[N（SiMe3）2]Na（THF） } 2 （2） in nearly quantitative yields. Both complexes 1 and 2 were well characterized by elemental analysis, IR spectra, ^1H and ^13C NMR spectra, and X-ray diffraction. It was found that the guanidinates adopt different coordination modes in these complexes.     

Reactions of Metal Salts and Alkali Metal Nitrates. Role of the Metal Precursors and Alkali Metal Ions in the Resulting Phase of Zirconia

Zirconia powders are prepared by reaction of a zirconium precursor with an alkali metal nitrate. The major part of the reactions takes place before the melting points and then the reactions go slowly to completion at 450°C in the molten salts. The roles of the precursor and the alkali metal ion are discussed considering the reaction between two precursors, octahydrated zirconium oxychloride and zirconium tetrachloride, and two nitrates, LiNO₃ and NaNO₃, and some resulting physico-chemical differences. The obtained zirconia powders contain very small amounts of alkali metal ions which act as stabilizing agent. Their effect on the balance tetragonal-monoclinic ZrO₂ depends upon the homogeneity of their distribution which is related to their ability to diffuse inside the bulk of particles and their polarizing power when located mainly on the surface.     

Topological Research on Standard Entropies of Alkali and Alkaline Earth Metal Compounds

The ionic polarizable ability parameter is definedasgi. The connectivity index of the polarizable abiltym G is introduced fromgiand based on the adjacency matrix of molecular topological graph. Because different ions should not have the same oxidation number or the same main quantum numbers, 0G、1G amongm G have good structural selection for inorganic molecules. The 0G and 1G of 64 alkali and alkaline-earth metal oxide halide, sulfide, selenide and telluride are calculated. The result shows: the 0G and 1G all have a positive correlation with the atomic number and size of molecules, but have a negative correlation with the atomic ploarizable ability in molecules. Since the standard entropy of compound increases with the atomic number of compounds an decreases with the atomic ploarizable ability, the standard entropies of compounds have a positive correlation with the 0G and 1G of compounds. The standard entropies of 64 alkali and alkaline-earth metal oxide, halide sulfide and selenide are correlated with the0Gand1Gof these compounds.     

Heats of Mixing of Aqueous Solutions of Alkali Metal Salts of Substituted Benzenesulfonic Acids

The enthalpy change on mixing aqueous solutions of substituted benzene sulfonic acids and their salts, with salts having a common cation or anion, were measured at constant total ionic strength and at 25°C. The results are qualitatively interpreted in terms of solute–water structural properties and the ion size effect. The heat effects of mixing solutions having common anions obey the sign rule of Young and Smith. In anion–common cation mixings at concentration of 0.5 mol-kg^–1 only exothermic heat effects were observed, whose magnitude increase with the increasing difference in size of the mixed anions. The magnitude of the mixing effect increased with the salt concentration in cation–common anion mixing processes, In anion–common cation mixings the enthalpy of mixing changes sign from negative to positive, indicating a predominantly endothermic effect as concentration increases.     

Structures of Organo Alkali Metal Complexes and Related Compounds

The investigation of the reactivity and structure of organometallic compounds of alkali metals has experienced a blustering development in the last decades. This class includes compounds that are especially important for our understanding of chemical bonding and also quite simple, for example methyl alkali metal complexes, whose structures have been unequivocally determined. Organometallic compounds of alkali metals (and also magnesium) generally exist as ion aggregates whose properties can be significantly modified through solvation by, for example, ether or amines. Important advances in the synthesis of new compounds, especially those of the heavier alkali metals, have been based on these results. It was long believed that the alkali metals had little tendency to undergo coordination and that their coordination chemistry would offer few surprises. This picture has now changed completely. Results from crystal structure investigations have revealed a variety of often surprising structure types (rings, heterocubanes, chains, layers, etc.) not only with the organometallic compounds but also with the amides, imides, alkoxides, phenoxides, enolates, and even halides. A comparison reveals interesting similarities between compounds that appear to be so different and leads to a general classification of the structure types possible with C, N, O, and halo ligands.     

Synthesis and Structural Investigation of a Complete Series of Brightly Colored Alkali Metal 1,3-Dimethylviolurates

A complete series of alkali metal 1,3-dimethylviolurates M(Me₂Vio) was synthesized and fully characterized. The title compounds M(Me₂Vio)(H₂O) [M = Li ( 3 ), Na ( 4 )], K(Me₂Vio)(H₂O)_0.5 ( 5 ) and M(Me₂Vio) [M = Rb ( 6 ), Cs ( 7 )] were prepared by neutralizing 1,3-dimethylvioluric acid (= HMe₂Vio; 2 ) with 1 equiv. of the corresponding metal hydroxides MOH. The resulting salts exhibit striking colors ranging from orange-red ( 3 ) through purple ( 4 , 5 ) to bright blue ( 6 , 7 ). In contrast to the monohydrate 4 , the classical synthesis of sodium 1,3-dimethylviolurate from 1,3-dimethylbarbituric acid and NaNO₂ afforded the purple trihydrate Na(Me₂Vio)(H₂O)₃ ( 4a ). All new compounds have been fully characterized by their IR and NMR (¹H, ¹³C) spectra as well as elemental analyses. X-ray crystal structure determination revealed that the title compounds exist as one- (Li, Na), two- (K, Cs), or three-dimensional (Rb) coordination polymers in the solid state.