An unusual o-metallated pyridyl dirhodium(II) complex: [Rh2{μ-(C5H3N)NH(C5H4N)}2{η2-(C5H4N)NH(C5H4N}2]Cl2·CH3OH

Reaction of Rh₂(O₂CMe)₄ and bis(2-pyridyl)amine, Hdpa, followed by addition of CH₂Cl₂ led to replacement of the acetate groups by Hdpa and orthometallation of two Hdpa pyridyl groups. The isolated complex, [Rh₂{μ-(C₅H₃N)NH(C₅H₄N)}₂{η²-(C₅H₄N)NH(C₅H₄N}₂]Cl₂ (1), has been characterized by X-ray crystallography, showing that the complex has two equatorially bound Hdpa groups and two bridging orthometallated dpa anions.     

Semi-rigid N-para-ferrocenyl(benzoyl)amino-acid esters for biomaterials: synthesis and characterization of Fc-C6H4CONHCH(R)CO2Me where Fc = (η5-C5H5)Fe(η5-C5H4) and R=H,CH3,CH2CH(CH3)2,CH2C6H5 and the X-ray crystal structures of Fc-C6H4CO2Me and the l-alanine derivative Fc-C6H4CONHCH(CH3)CO2Me

A series of N-para-(ferrocenyl)benzoyl amino-acid esters, para-Fc(C₆H₄)CONHCH(R)CO₂CH₃ {Fc = (η⁵-C₅H₅)Fe(η⁵-C₅H₄); R = H, CH₃, CH₂CH(CH₃)₂, CH₂C₆H₅}, 3–6 have been prepared by coupling para-(ferrocenyl)benzoic acid to the amino-acid esters (gly, l-Ala, l-Leu, l-Phe) using the standard 1,3-dicyclohexylcarbodiimide (DCC), 1-hydroxybenzotriazole (HOBt) protocol. The compounds were fully characterized by a range of spectroscopic techniques including FAB-MS. The X-ray crystal structures of the parent para-(ferrocenyl)benzoyl methyl ester, Fc-C₆H₄CO₂Me, 1 and a chiral derivative N-{para-(ferrocenyl)benzoyl}-l-alanine methyl ester, Fc-C₆H₄CONHCH(CH₃)CO₂Me, 4 have been determined.     

A fast route to the potential biological reagent (η5-C5H4COOH)Re(CO)3 from [NH4] [ReO4]

The rhenium carbonyl carboxylic acid (η⁵-C₅H₄COOH)Re(CO)₃ (Re + 1) is readily accesssible in a rapid fashion starting from perrhenate (Re + 7). This complex can be conjugated to amino acids and proteins opening the way to a robust small radiopharmaceutical.     

[C16H33N(CH3)3]3[PO4(WO3)4]催化脂肪酸甲酯环氧化性能

在无酸、无溶剂条件下,以[C₁₆H₃₃N(CH₃)₃]₃[PO₄(WO₃)₄]为反应控制相转移催化剂,研究各因素对脂肪酸甲酯(FAME)环氧化反应的影响。结果表明,水相pH对环氧化反应的影响最大,反应适宜pH为4;适宜反应条件为过氧化氢与脂肪酸甲酯中双键摩尔比为1.05:1,反应温度50～60℃,反应时间5 h。在此反应条件下催化剂循环5次不失活,产品环氧值大于4.0%,碘值小于5 g I·(100 g)^-1。并通过元素分析与红外光谱,研究了催化剂在反应过程中的变化,认为磷钨杂多阴离子的分解是导致催化剂失活的关键原因。     

A convenient method for the synthesis of [Pd{[(η5-C5H3)–CHN–(CH2)2–NMe2]Fe(η5-C5H5)}Cl] and the study of its reactivity with diphosphines

A one-pot method for the preparation of [Pd{[(η⁵-C₅H₃)–CHN–(CH₂)₂–NMe₂]Fe(η⁵-C₅H₅)}Cl] is described. Its X-ray crystal structure and its reactions with the diphosphines Ph₂P–(CH₂)_n–PPh₂ {with n=1 (ddpm) or 2 (dppe)} are also reported.     

Variations in binding modes of 2-mercaptobenzoxazolates in the novel cyclic trinuclear complexes [Mn3(CO)10(μ-SCNOC6H4)3] and [Re3(CO)12(μ-SCNOC6H4)3]

From reactions of [M₂(CO)₈(MeCN)₂] (MMn, Re) with 2-mercaptobenzoxazol, trinuclear clusters [Mn₃(CO)₁₀(μ-SCNOC₆H₄)₃] and [Re₃(CO)₁₂(μ-SCNOC₆H₄)₃] have been isolated; the former contains 2-mercaptobenzoxazolate ligands in three different binding modes, while in the latter all three bridge rhenium centres by S,N-coordination, but the three rhenium atoms all have different coordination environments.     

[Ru(CO)(CH3CO2)(tpa)]ClO4·C6H5CH3 (tpa=tris(2-pyridylmethyl)amine), the first ruthenium carbonyl complex of tpa

The reaction of dodecacarbonyltriruthenium with tris(2-pyridylmethyl)ammonium perchlorate (tpa·3HClO₄), in the presence of acetic acid, afforded a new ruthenium complex of tpa, [Ru(CO)(CH₃CO₂)(tpa)]ClO₄·C₆H₅CH₃ (1). Compound 1 has been characterized by X-ray structural analysis, IR and ¹H NMR spectra.     

A Novel Mixed-Valence Tetranuclear Iron-Oxygen Clusters in the Organically Templated Iron Phosphate [H3N(CH2)2NH3]2 Fe4O(PO4)4 ċH2O

A novel iron phosphate templated with ethylenediammonium cation, [H₃N(CH₂)₂NH₃]₂ Fe₄ O(PO₄)₄H₂O, has been synthesized hydrothermally and characterized by single-crystal X-ray diffraction, thermo-gravimetric analysis, magnetic susceptibility and Mossbauer spectroscopy. The compound crystallizes in the mono-clinic space group C2 with a= 30.3801(5),b= 10.1204(5),c= 10.0977(5) Å, = 107.712(1)°, V = 2957.5(4) ų and Z = 6. The structure contains 5 and 6-coordinated Fe atoms bridged by ₄-oxygen and PO₄ groups to form two types of mixed-valence Fe₄P₄ cubane-like clusters, which are connected via Fe- O- P bonds to give rise to intersecting channels that house the ethylenediammonium cations and water molecules. Room-temperature Mossbauer data confirm the presence of Fe^II and Fe^III.     

The first carbamoyl–carboxylate complex of transition metals: Synthesis and structure of {(OC4H8NH)[OC4H8NC(O)]Pd}2(μ-CMe3CO2)2

Reactions of palladium(I) carbonyl carboxylate complexes [Pd(μ-CO)(μ-RCO₂)]_n with secondary amines on the example of morpholine were studied. It was found that intramolecular carbonylation of amine in coordination sphere of polynuclear palladium species proceeds and binuclear palladium carbamoyl complex {(OC₄H₈NH)[OC₄H₈NC(O)]Pd}₂(μ-RCO₂)₂ forms as a result. This is the first structurally characterized carbamoyl–carboxylate complex of transition metals. Also it was shown that morpholine itself and carboxylate-anions act as proton acceptors in the reaction of carbonylation of morpholine by coordinated CO.     

[Ba(TEA)2](CH3CO2)2热分解性质的研究

利用热重分析法、差热分析法、X射线衍射法和红外光谱分析法研究了[Ba(TEA)2](CH3CO2)2的热分解性质。研究发现,在含氧气氛中加热到1200℃,[Ba(TEA)2](CH3CO2)2的分解过程经历了四个阶段。初始样品在熔化之后,在155℃至265℃之间首先分解生成了Ba(CH3CO2)2。而在390℃至480℃的温度区间内,Ba(CH3CO2)2的分解被分成两个步骤;在390℃时,Ba(CH3CO2)2首先分解生成BaC2O4,随后BaC2O4继续分解生成了α-BaCO3;在811℃左右,α-BaCO3相变转化为β-BaCO3。随着温度的升高,伴随着CO2气体的产生,β-BaCO3被最终分解得到BaO。     

混合配体配合物[Co3(BTC)2(Lb)2(CH3CH2OH)2·4H2O]n的合成与晶体结构

以1,3,5-均苯三甲酸(H_3BTC)、2-[1-(2-吡嗪基)乙缩醛腙(L_a)、醋酸钴、为原料采用水热法合成了配合物[Co_3(BTC)_2(L_b)_2(CH_3CH_2OH)_2·4H_2O]_n(1)(L_b=2-乙酰基吡嗪缩水合肼)。配合物晶体属单斜晶系,空间群C2/c。X-射线单晶衍射结果表明:两个Co~(2+)离子与氧原子、氮原子配位,均为变形八面体构型。席夫碱配体在配位过程中分解为2-乙酰基吡嗪缩水合肼,BTC~(3-)配体全部去质子化且以μ_4-的配位模式将两个Co~(2+)连接成6-连接的三维结构。晶胞参数:a=15.146(9)?,b=13.417(8)?,c=23.564(18)?,β=90.087(8)°,V=4789(5)?~3,Z=4。     

酸性离子液体[N4H4(CH2)6].4HSO4催化合成氯乙酸乙酯的研究

以六次甲基四胺和浓硫酸为原料制备了酸性离子液体[N4H4(CH2)6].4HSO4,将其应用到氯乙酸乙酯的合成中,并对酯化反应涉及的工艺参数进行了优化,采用核磁共振波谱对产物进行了表征。结果表明：n（氯乙酸）：n（乙醇）=1:1.8,离子液体用量为氯乙酸总质量的30%,反应温度100℃,反应时间3.5h,氯乙酸乙酯收率为93.27%。重复使用6次,氯乙酸酯收率为90.16%。产品易分离,克服了无机酸催化的缺陷。     

A solvothermal synthesis of a novel 1D ladder-like (NH3CH2CH2NH3)AgAsS4 containing N–H⋯S hydrogen bonding

A one-dimensional compound (NH₃CH₂CH₂NH₃)AgAsS₄ with ladder-like chains was synthesized solvothermally. This compound crystallizes in the monoclinic system, space group C2/c, with a=13.5805(8) Å, b=6.5331(3) Å, c=22.7711(9) Å, α=90°, β=106.42(3)°, γ=90°, Z=8. The rare type hydrogen bonding of N–H⋯S and electrostatic force hold the anionic chains together.     

Synthesis,structure and characterization of (NH4)2[Cu2(H2O)4(NH3CH2COO)2(NH2CH2COO)2]H2V10O28·6H2O

The decavanadate with a novel glycine–glycinato complex of copper (II) in the cationic part, (NH₄)₂[Cu₂(H₂O)₄(NH₃CH₂COO)₂(NH₂CH₂COO)₂]H₂V₁₀O₂₈·6H₂O (1), has been prepared and characterized by elemental analysis, infrared and EPR spectroscopies. The triplet X band EPR spectrum of powdered sample evidenced magnetic interaction between the Cu(II) atoms in the dimeric unit which is probably realized through the bridging water molecules in this part of the complex. A single crystal X-ray diffraction study revealed that the structure of 1 contains cationic copper complex with a rare Cu(H₂O)₂Cu double bridge. In this cation, a simultaneous bidentate N, O– and monodentate O– coordination of glycine to the same central atom was observed for the first time.     

H2S–CO2 Separation Using Room Temperature Ionic Liquid [BMIM][Br]

Solubility and selective absorption of hydrogen sulfide (H₂S) over carbon dioxide (CO₂) in a room temperature ionic liquid, 1-butyl-3-methylimidazolium bromide ([BMIM][Br]) has been evaluated under ambient temperature and pressure. [BMIM][Br] demonstrated its potential as a solvent for selective removal of H₂S from CO₂/H₂S mixture. Our investigation indicated that H₂S solubility in [BMIM][Br] is comparable to or better than that in commercially available MDEA-based solvents. Meanwhile, CO₂ solubility in [BMIM][Br] is lower than that in the same amine resulting in H₂S/CO₂ absorption selectivity of within 3.5 to 3.75. The solubility behavior is relatively maintained after 4 times absorption-desorption cycles. A computational molecular study suggested that intramolecular hydrogen bonding interaction between anion Br and hydrogen atom of H₂S could stabilize the complex and resulted lower complexation energy than CO₂ interaction with [BMIM][Br]. Based on the experiment results, a separation process employing [BMIM][Br] is proposed to control the CO₂/H₂S ratio existing in a natural gas feed.