无机化学中的脱水缩合反应

将无机化学中的脱水缩合反应进行分类:发生在无机含氧酸之间的脱水缩合反应;发生在无机含氧酸酸式盐之间的脱水缩合反应和酸化含氧酸盐溶液而发生的脱水缩合反应。介绍了缩合反应及缩合反应产物的应用。     

Knoevenagel缩合反应研究的新进展

综述了近年来Knoevenagel缩合反应研究的新进展, 包括微波、超声波、固相合成、离子液体等新技术新试剂在该反应中的应用.     

呋喃甲酸酯与三氯乙醛缩合反应研究

系统地研究了呋喃甲酸酯与三氯乙醛的缩合反应规律，提出了路易斯酸催化该反应的机制。当呋喃酸酯：无水三氯乙醛：三氯化铝（摩尔比）为２：１：１时，在６０～７０℃下反应６ｈ双分子缩合产物的收率为５３～７５％。     

共轭烯酸与聚乙二醇缩合反应研究进展

聚乙二醇不饱和酸酯是一类重要的高聚物单体,其与其他单体接枝共聚也可合成多功能化的高分子聚合物.主要综述了聚乙二醇与丙烯酸、甲基丙烯酸、马来酸等共轭烯酸缩合反应的研究进展,并对其发展进行了展望.     

缩合反应

如果把脱去小分子,H2O,HCI,NH3等叫做缩合反应,那么醋化、消去、硝化等均具有缩合特征。缩合的前提是分(离)子中含有可缩去小分子的“基团”,分(离)子中所含这些“基团”的数目,表明它有几次缩合的机会。先讨论含氧酸的缩合。     

呋喃甲酸醋与三氯乙醛缩合反应研究

系统地研究了呋喃甲酸酯与三氯乙醛的缩合反应规律，提出了路易斯酸催化该反应的机制。当呋喃甲酸酯：无水三氯乙醛：三氯化铝（摩尔比）为２：１：１时，在６０～７０℃下反应６ｈ，双分子缩合产物的收率为５３～７５％。     

钛钼异双核配合物的合成及结构研究

合成了13个钛-钼异双核金属有机配合物,测定了它们的碳、氢、氮、钛及钼的含量,还测定了~1H、~(13)C、~(11)B及~(95)Mo NMR和红外、质谱、电导数据.确认该类配合物分子中存在Ti-Mo之间的金属-金属键和一个桥羰基键,并具有如下结构:其中R=H,Pz(吡唑基);R'=CH_3,OCH_3,OC_2H_5;X=H,CH_3;Y=H,CH_3.     

氨基二苯硒的酰化和缩合反应研究

４－氨基二苯硒分别与酸酐和醛进行酰化反应和缩合反应，合成了６种Ｎ－二苯硒胺羰基苯甲酸及１２个，Ｎ－二苯硒亚胺化合物，用元素分析，红外光谱，核磁共振谱表征了结构，结果表明在酰化反应和缩合反应中，４－氨基二苯硒与芳伯胺及氨基二茂铁的作用相同，产物结构类似，且均具有生物活性。     

安息香缩合反应的影响因素

安息香缩合反应是重要的有机化学实验,影响实验的因素较复杂。本文通过反应温度、反应时间、pH、反应物料的投入方式等对安息香合成的影响进行了探讨。实验结果表明：反应温度、反应时间、pH是影响反应的重要因素,而反应前是否对反应物进行冷却以及苯甲醛与NaOH溶液的投料顺序对反应的影响不大。     

乙基二茂铁与乙酰丙酸甲酯的缩合反应

以多聚磷酸-浓硫酸-甲醇为催化剂和环已烷为溶剂,由乙基二茂铁与乙酰丙酸甲酯缩合合成4,4-双（乙基二茂铁基）成酸甲酯,转化率73%,产率84%。正交实验法获得的适宜反应条件：乙基二茂铁55mmol,乙酰丙酸甲酯75mmol,浓硫酸3.0mL,环已烷20mL,甲醇11mL。通过元素分析、IR、^1H NMR和^13C NMR确证了缩合产物的结构。     

Dimolybdenum Complexes Containing Pairs of Bridging Diphosphine and Carboxylate Ligands. Synthesis and Structures of trans-Mo2(O2CCH3)2(μ-dppa)2(BF4)2 and trans-Mo2X2(O2C(CH2)nCH3)2(μ-dppa)2 (n = 2, 10 or 12; X = Cl or Br; dppa = N,N-Bis(diphenylphosphino)amine)

The red complex trans-Mo₂(O₂CCH₃)₂(μ-dppa)₂(BF₄)₂, 1 , was prepared by reaction of [Mo₂(O₂CCH₃)₂(CH₃CN)₆][BF₄]₂ with dppa (dppa = Ph₂PN(H)PPh₂) in THF. The reactions of Mo₂(O₂C(CH₂)_nCH₃)₄ with dppa and (CH₃)₃SiX (X = Cl or Br) afforded the complexes trans-Mo₂X₂(O₂C(CH₂)_nCH₃)₂(μ-dppa)₂ (X = Cl, n = 2, 2; X = Br, n = 2, 3; X = Cl, n = 10, 4 ; X = Cl, n = 12, 5 ). Their UV-vis, IR and ³¹P{¹H}-NMR spectra have been recorded and the structures of 1, 2 and 3 have been determined. Crystal data for 1 : space group P2₁/n, a = 12.243(1) Å, b = 17.222(1) Å, c = 13.266(1) Å, β = 95.529(1)°, V = 2784.1(6) ų, Z = 2, with final residuals R = 0.0509 and Rw = 0.0582. Crystal data for 24CH₃Cl₂: space group P2₁/n, a = 13.438(1) Å, b = 19.276(1) Å, c = 14.182(1) Å, β = 111.464(1)°, V = 3418.9(6) ų, Z = 2, with final residuals R = 0.0492 and Rw = 0.0695. Crystal data for 3·4CH₂Cl₂: space group P2₁/n, a= 13.579(1) Å, b = 19.425(1) Å, c = 14.199(1) Å, β = 111.881(2)°, V = 3475.6(7) ų, Z = 2, with final residuals R = 0.0703 and Rw = 0.0851. Comparison of the structural data shows that the effect of the axial ligand on weakening the Mo-Mo bond strength is X^? > CH₃CN > BF₄^?. The T_m values are 121.7 °C for 2 , 111.1 °C for 3 and 91.5 °C for 5 , respectively.     

Syntheses and crystal structures of Dimolybdenum complexes containing P2 and functionalized Cyclopentadienyl ligands

The dimolybdenum complex [(η⁵-RC₅H₄)₂Mo₂(CO)₆] (1, R = CH₃CO; II, R = CH₃O₂C) reacts with an equimolar amount of white phosphorus P₄ to yield the corresponding dimolybdenum complex containing the P₂ ligand [(η⁵-RC₅H₄)₂Mo₂(CO)₄(μ,η²-P₂)] (1, R = CH₃CO; 2, R = CH₃O₂C) in moderate yield. The two new compounds have been characterized by elemental analyses, ¹H?NMR, ¹³C?NMR, ³¹ P?NMR and IR spectroscopies and their crystal structures have been determined by X-ray diffraction methods.     

The Reaction of the Betain‐like Compound O2C2(PPh3)2 with [(cod)PtI2] – Crystal Structure of the Salt (HC{PPh3}2)[(η3‐C8H11)PtI2]

The reaction of the betain‐like compound O₂C₂(PPh₃)₂ ( 1 ) with [(cod)PtX₂] in THF solution gives the salt‐like compounds (HC{PPh₃}₂)[(η³‐C₈H₁₁)PtX₂] ( 3 , X = I; 4 , X = Cl) in about quantitative yields. The new η³‐bonded C₈H₁₁ ligand is the result of a proton transfer from the coordinated cod ligand to 1 with subsequent release of CO₂. The X‐ray analysis of 3 shows the presence of two isomers in a 60:40 ratio, which differ in the bonding of the C₈H₁₁ ligand. 3 crystallizes in the triclinic space group with the unit cell dimensions a = 1091.7(1), b = 1141.5(1), c = 1649.4(2) pm; α = 80.34(1)°, β = 83.62(1)°, γ = 89.03(1)°, V = 2013.7(4)·10⁶ pm³, Z = 2.     

The Reaction of the cis-ReO2 + Core with 2-Amino-3-Methylbenzoic Acid

The reaction of a twofold molar excess of 2-amino-3-methylbenzoic acid (H₃amb) with cis-[ReO₂I(PPh₃)₂] in ethanol led to the isolation and characterization of the six-coordinate [Re(amb)(OEt)I(PPh₃)₂] (1). The X-ray crystal structure of 1 illustrates that the trianionic ligand amb acts as a bidentate chelate via the doubly deprotonated amino nitrogen, which is present in 1 as an imide, and the deprotonated acetoxy oxygen. The Re=N bond length is 1.751(3)?Å, and the Re=N–C angle [143.6(3)°] deviates considerably from linearity.     

The structure and magnetic properties of μ_3-oxotriiron(Ⅲ) complex [Fe_3O(OBz)_6(CH_3OH)_3](NO_3)(CH_3OH)_2

A new μ3-O triiron(Ⅲ) complex [Fe_3O(OBz)_6(CH_3OH)_3](NO_3)(CH_3OH)_2 (HOBZ = benzoic acid) has been synthesized, its structure has been determined and variable temperature magnetic susceptility has also been measured. In the molecule, three iron atoms formed an equilateral triangle with u_3-O in center. The fitting to the magnetic susceptibility showed that an intramolecular antiferromagnetic exchange interaction occurred between iron atoms with J=-25.51 cm~(-1), and a weaker intermolecular antiferromagnetic exchange interaction occurred with zJ' = -2.30cm~(-1).     

微环境条件影响的光化学反应研究进展

对近年来微环境条件影响的光反应化学反应研究和一综合评述，包括主体－客体络合物，晶格控制物Ｌｅｗｉｓ酸络合物，电荷转移络合物，胶束以及吸附在硅胶或分子筛表面等体系光化学反应方面取得的重要成果，这类微环境条件影响的光化学反应具有较高的选择性和专一性，参考文献１５篇。     

Design and Self-assembly of a Novel Tetranuclear Zinc(Ⅱ) Complex via Reaction of 1,3-Thiazolidine-2-thione (tzdtH) with Zn(NO3)2

Introduction The self-assembly of clusters in inorganic systems is an interesting subject. The self-assembly of big molecules has been well established in biological systems[1-5].     

Study on the synthesis and crystal structure of tetrahyhrated tetraaquotris(4-mono-chloroacetylantipyrine)samarium (III) perchlorate

Based in the phase equilibrium study of the system Sm(C1O₄)₃-4-monochloroacetytantipyrine (C₁₃H₁₃ClN₂O₂)-H₂O at 30°C, we have synthesized the title complex [Sm(C₁₃H₁₃Cl-N₂O₂)₃(H₂O)₄](ClO₄)₃-4H₂O. The single crystal structure analysis on RASA-IIS Rigaku diffractometer shows that the coordination number of the metal ion is nine and the geometry of the complex is tricapped trigonal prism. Two of the three molecules of organic ligand act as bidentate chelated through both carbonyl oxygens to the metal ion, but the other one as a monodentate coordinated only through the ring carbonyl oxygen, the side chain carbonyl is far away from the central ion. The crystal is monoclinic, space group P2₁, α = 18.013(4), b = 14.709(3), c = 10.536(3) Å, β=94.69(2)°, V=2782(1) ų, Z=2.     

Methylation sites in tris(μ-thiolato)dimolybdenum(III) complexes

Attempts at methylating cis-[Mo₂Cp₂(μ-SMe)₃L₂](BF₄) [Cp = η⁵-C₅H₅; L = CO (1a) CNxyl (1b), CNBu^t (1c), NCMe (1d)] with methyl triflate gave the corresponding thioether-bridged cations [Mo₂Cp₂(μ-SMe)₂(μ-SMe₂)L₂]²⁺ (4²⁺), except in the case of 1a which did not react at room temperature. The electronic properties of the ancillary ligands L thus have a crucial influence on the course of this reaction. The dimeric compounds [Mo₂Cp₂(μ-SMe)₃(CNBu^t)(CN)] (2) and [Mo₂Cp₂(μ-SMe)₃{μ-η¹-NC(CH₃)CH₂CN}] (3), which potentially offer the alternatives of S- or N-methylation, reacted with methylating agents to give mainly the S-methylated derivatives 5 and 7. Only in the case of the nucleophilic reactant 2 was N-methylation also observed and isomer 6 was obtained as a minor product together with 5. New complexes have been completely characterised by multinuclear NMR, IR and elemental analysis, supplemented for 5 by X-ray diffraction study at 100 K.     

(t-BuCp)2YbCl·THF的合成和晶体结构

我们曾报道利用叔丁基环戊二烯基作配体,可分离得到二叔丁基环戊二烯基轻稀土氯化物,并测定了(t-BuCp)_2PrCl·2THF 的分子结构,与此同时,wayda 报道了叔丁基环戊二烯基中、重稀土氯化物的合成,但未能得到这些配合物的结构。本文用叔丁基环戊二烯钠与无水 YbCl_3以2∶1摩尔比在四氢呋喃中反应,分离得到了中性二叔丁基环戊二烯基氯化镱四氢呋喃配合物,并测定了它的 X 光晶体结构。