氯化铜的少溶剂固态连串配位化学反应

在少量水的存在下,由于NH₄[CuCl₃]对水不稳定,CuCl₂·2H₂O与氯化铵的配位化学反应只能得到1∶2产物(NH₄)₂[CuCl₄(H₂O)₂];但在无水乙醇中,无水CuCl₂与氯化铵按1∶1或1∶2的物质的量之比混合时,能相应地得到NH₄[CuCl₃]或(NH₄)₂[CuCl₄]。CuCl₂·2H₂O与2,2''-联吡啶(bipy)的少溶剂固态化学反应仍能像固态化学反应一样,根据反应物的配比生成相应的唯一产物,但在物质的量之比为1∶1的反应中发现1∶2产物曾经形成。热力学分析说明,如果连串反应的后一步的Δ_rG^⊖大于前一步的,则上述反应现象是可能的。     

Nine-coordinate rare earth metal complexes with aminopolycarboxylic acids: Mononuclear (NH4)3[TbIII(ttha)]·5H2O and binuclear (NH4)4[Tb 2 III (dtpa)2]·9H2O

The two title coordination compounds, (NH₄)₃[Tb^III(ttha)]·5H₂O (ttha = triethylenetetramine-N,N,N′,N″,N‴,N‴-hexaacetic acid) and (NH₄)₄[Tb ₂ ^III (ttha)]·9H₂O (dtpa = diethylenetriamine-N,N,N′,N″,N″-pentaacetic acid), have been prepared and characterized by FT-IR, elemental analyses, TG-DTA and single crystal X-ray diffraction techniques. The (NH₄)₃[Tb^III(ttha)]·5H₂O compound is monoclinic, P2₁/c; a = 10.398(1) Å, b = 12.791(1) Å, c = 23.199(2) Å; β = 90.914(2)°; V = 3084.9(5) ų; Z = 4; D _calc = 1.704 g/cm³; μ(MoK _α ) = 2.376 mm^™; R = 0.023 and wR ² = 0.049 for 5429 observed reflections with I ≥ 2σ(I). The [Tb^III(ttha)]³⁻ complex anion in the crystal has a nine-coordinate mononuclear molecular structure with pseudo-monocapped square-antiprismatic configuration. The (NH₄)₄[Tb ₂ ^III (dtpa)₂]·9H₂O compound is triclinic, P-1; a = 9.739(1) Å, b = 10.010(1) Å, c = 12.968(2) Å; α= 85.890(2)°, β = 77.338(2)°, γ = 77.587(2)°; V = 1204.2(2) ų; Z = 1; D _calc = 1.832 g/cm³; μ(MoK _α ) = 3.015 mm^™; R = 0.024 and wR ² = 0.060 for 4750 observed reflections with I ≥ 2σ(I). The [Tb ₂ ^III (dtpa)₂]₄₋ complex anion has a binuclear structure in the crystal; the two Tb^III centers are equivalent and have a nine-coordinate environment with the same pseudo-tricapped trigonal-prismatic configuration. The thermal analysis revealed that the coordination cores of the (NH₄)₃[Tb^III(ttha)]·5H₂O and (NH₄)₄[Tb ₂ ^III (dtpa)₂]·9H₂O compounds are stable up to 221°C and 252°C, respectively. Original Russian Text Copyright ? 2008 by J. Wang, X. Zh. Liu, X. F. Wang, G. R. Gao, Zh. Q. Xing, X. D. Zhang, and R. Xu The text was submitted by the authors in English. Zhurnal Strukturnoi Khimii, Vol. 49, No. 1, pp. 81–89, January–February, 2008.     

Transformations of high spin MnII and FeII polymeric pivalates in reactions with pivalic acid and o-phenylenediamines

The thermolysis and reactions of the polymeric high spin Mn^II and Fe^II complexes [Mn(μ-OOCBu^t)₂(HOEt)]_n (1) and [Fe(μ-OOCBu^t)₂]_n (3) with pivalic acid and o-phenylenediamines 1,2-(NH₂)₂C₆H₂R₂ (R = H or Me) were studied. The synthesis of compound 1 performed with a deficiency of pivalate anions affords the antiferromagnetic chloropivalate polymer { (MeCN)(HOOCBu^t)(H₂O)Mn₅Cl(OH)(OOCBu^t)₈·MeCN}_n. The reaction of 1 with an excess of pivalic acid produces the antiferromagnetic polymer [Mn₄(OOCBu^t)₈(HOOCBu^t)₂]_n. The analogous reaction of pivalic acid with polymer 3 gives the mononuclear complex Fe(η ¹-OOCBu^t)₂(η¹-HOOCBu^t)₄ containing the high spin iron(II) atom as the major product. Study of the reactions of 3 with a deficiency (<1: 1) and an excess (>1: 1) of diamines demonstrated that the polymer {[(η²-(NH₂)₂C₆H₄)₂Fe(μ-OOCBu^t)₂][Fe₂(μ-OOCBu^t)₄] · · 2MeCN}_n is generated as the major product in the former case, whereas the mononuclear complexes Fe(η¹-OOCBu^t)₂[η¹-(NH₂)₂C₆H₄]₄ and Fe(η¹-OOCBu^t)₂[η²-(NH₂)₂C₆H₂Me₂][η¹-(NH₂)₂C₆H₂Me₂]₂ are predominantly obtained in the latter case. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 779–792, May, 2006.     

钴(Ⅲ)-胺配合物模板导向合成系列稀土金属草酸盐化合物

水热条件下,以钴(Ⅲ)-胺配合物[Co(en)₃]³⁺,[Co(dien)₂]³⁺为模板,合成出了3例新的稀土草酸盐化合物{[Co(en)₃]·[KLa₂(C₂O₄)₅(H₂O)₆]·H₂O}_n (HNU-9)、{[Co(dien)₂][La₂(C₂O₄)₄(H₂O)₂]·xH₂O}_n (HNU-11)和{K₃[Co(dien)₂][La₄(C₂O₄)₉(H₂O)₂]·5H₂O}_n (HNU-12)。在这3个化合物中,不同的模板剂(Co(en)₃³⁺,Co(dien)₂³⁺,K⁺+Co(dien)₂³⁺)以不同的方式存在于这些化合物中,从而构筑出不同拓扑结构的三维骨架结构。有意思的是,由于中心金属原子La的配位模式不同,HNU-11和HNU-12展现出未报道过的新颖的拓扑结构。可见,具有高配位数的中心稀土金属原子较易构筑出具有新颖拓扑结构的化合物。     

二维Cd(Ⅱ)配合物的晶体结构及其对对硝基苯酚、四环素、2,6-二氯-4-硝基苯胺的荧光识别

通过水热反应合成了一种 Cd(Ⅱ)配合物, 分子式为{(H₂dbim)_0.5[Cd(Hbptc)]·H₂O}_n (1), 其中 dbim=1-(4-(2, 6-二甲基-2H-苯并[d]咪唑-3(3H)-酰基)甲基)苄基)-2, 7-二氢-2, 5-二甲基-1H-苯并[d]咪唑, H₄bptc=3, 3'', 4, 4''-二苯甲酮四羧酸。配合物 1为 2D层状结构, 点符号为{4⁴·6⁶}。配合物 1可用于一些常见环境污染物的荧光识别。研究结果表明, 配合物 1能有效检测对硝基酚、四环素、2, 6-二氯-4-硝基苯胺。计算得到对硝基苯酚、四环素和 2, 6-二氯-4-硝基苯胺对 1的猝灭常数分别为 2×10²、5.4×10⁴和 2×10⁴ L·mol^-1。     

基于醚氧桥联四羧酸配体构筑的三个钴(Ⅱ)、铜(Ⅱ)和镉(Ⅱ)配位聚合物的合成、结构和在Knoevenagel缩合反应中的催化性质

采用水热方法,选用醚氧桥联四羧酸配体H4dia与菲咯啉(phen)、2,2''-联吡啶(bipy)或双(4-吡啶基)胺(bpa)分别与CoCl₂·6H₂O、CuCl₂·2H₂O和CdCl₂·4H₂O在160℃下反应,得到了一个一维链结构[Co₂(μ₄-dia)(phen)₂(H₂O)₂]_n (1)和2个三维网络结构的配位聚合物[Cu₂(μ₆-dia)(bipy)₂]_n (2)和{[Cd₂(μ₅-dia)(μ-bpa)2(H₂O)]·H₂O}_n (3),并对其结构和催化性质进行了研究。研究表明,在50℃下配合物2在Knoevenagel缩合反应中显示出很好的催化活性。     

氰基桥联的Fe2Ni双之字链的合成与磁性

利用四氰基构筑单元和不同位阻的吡啶类配体,合成了3例氰基桥联的Fe₂^ⅢNi^Ⅱ链状化合物。化合物{[Fe（bpy）（CN）₄]₂[Ni（bp）₂]·2H₂O}_n（1）（bpy=2,2''-联吡啶;bp=4-苯基吡啶）,{[Fe（bpy）（CN）₄]₂[Ni（papy）₂]·H₂O}_n（2）（papy=4-（苯基氮烯）吡啶）和{[Fe（bpy）（CN）₄]₂[Ni（azp）]·4H₂O}_n（3）（azp=1,2-二（吡啶-4-基）二氮烯）均为双之字型的链状结构。磁性测试表明化合物1~3均表现为链内的铁磁相互作用。化合物1表现出单链磁体行为,有效能垒为10.9 K。     

咪唑-芳香多羧酸金属有机骨架化合物的合成、结构及性质

以5-(1H-咪唑)异酞酸(H₂L)为配体,在水热条件下合成了3个金属有机框架化合物:[PrL(HL)(H₂O)₂]·H₂O(1),Er(H_0.5L)₂(2)和[CoL(H₂O)₂]·H₂O(3)。单晶X-射线衍射测试结果表明,3个化合物都属于单斜晶系,P2₁/c空间群。化合物1中,Pr³⁺为九配位,而化合物2和3中,Er³⁺和Co²⁺均为六配位。在镧系配合物1和2中,配体中氮原子未参与配位。1为2D折叠形结构,2为3D框架结构。在过渡金属配合物3中,氮原子与Co²⁺配位,这有助于形成平面二维结构。化合物1和3通过分子间π-π堆积,进一步形成3D结构。3个化合物均展现出较好的热稳定性。     

Syntheses, spectra and crystal structures of a series of Mo/S(O) complexes containing oxalate ligand

Two Mo/S complexes: K₆[Mo₂O₂S₂(C₂O₄)₂-(ClPO₃)₂]·H₂O (1) and K₆[Mo₂O₃S(C₂O₄)₂(ClPO₃)₂]·3H₂O (2) containing oxalate ligand were prepared by the reaction of (NH₄)₂MoS₄ and potassium oxalate by adding a small amount of H₃PO₄ to adjust the value of pH in the system of methanol and water under an atmosphere of pure nitrogen at ambient temperature and characterized by means of elemental analysis, IR, and UV-Vis. Results of the analysis reveal that crystals of the complex 1 are orthorhombic, space group Pbcn, a = 4.6370(2) nm, b = 0.7549(2) nm, c = 1.3888(4) nm, V = 4.861(2) nm³, Z = 8, M = 945.49, Dc = 2.58 g/cm³, μ = 2.625 cm⁻¹, R = 0.063, and wR = 0.075. In addition, their spectral properties were also discussed. Translated from Chem. Res. Appl., 2006, 18(4) (in Chinese)     

Synthesis and structure of complex compound Rh(III) of (NH4)2[Rh(NO2)3(NH3)(µ-OH)]2 composition

The crystalline structure of a new compound Rh(III) of (NH₄)₂[Rh(NO₂)₃(NH₃)(μ-OH)]₂ composition has been determined. The crystallographic characteristics are H₁₆N₁₀O₁₄Rh₂: a = 6.3963(2) Å, b = 9.3701(4) Å, c = 13.6646(5) Å, β = 102.266(1)°, V = 800.28(5) ų, Z = 2, d _calc = 2.432 g/cm³. The distance Rh...Rh in the dimer is 3.200 Å. Original Russian Text Copyright ? 2006 by S. P. Khranenko, I. A. Baidina, and S. A. Gromilov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 47, No. 2, pp. 380–384, March–April, 2006.     

Towards click chemistry: Multicomponent reactions via combinations of name reactions

In this report, we try to show the importance of incorporation of name reactions in the sequential cascade reaction in which significantly decreasing the number of steps towards an ideal and practical multi-step synthesis of natural products as well showing virtually all the advantages already mentioned for “Click Chemistry”. In addition, since the chiral inductions are desired for most of these sequential name reactions, their asymmetric catalyzed reactions were also described.     

Recent advances in ionic liquids: green unconventional solvents of this century: part II

Abstract

In the second part of our paper, further recent developments of ionic liquids in selected name reactions of carbonyl chemistry such as Mannich, Reformatsky, Cannizaro, Streacker, Barbier, Pechmann, etc. are described.     

Competitive thermal ene reaction and Diels-Alder reactions of 2-[N-(alk-2-enyl)benzylamino]-3-vinylpyrido[1,2-a]pyrimidin-4(4H)-ones

Thermal reaction of 2-[N-(alk-2-enyl)benzylamino]-3-(2-substituted and 2,2-disubstituted)vinylpyrido[1,2-a]pyrimidin-4(4H)-ones gave azepine, the desired ene products, and/or pyran derivatives. The formation of the latter was responsible for the [4+2] cycloaddition reaction between the α,β-unsaturated ester carbonyl moiety as a diene part and the alkenylamino moiety as an ene one. The reaction features depended upon the kinds of substituents both on the vinyl and alkenyl counterparts; strongly electron-withdrawing substituents on the vinyl moiety or an electron-donating substituent on the alkenyl one changed the reaction feature from the ene reaction to the hetero Diels-Alder reaction.     

Palladium bis(2,2,6,6-tetramethyl-3,5-heptanedionate) catalyzed Suzuki, Heck, Sonogashira, and cyanation reactions

Palladium bis(2,2,6,6-tetramethyl-3,5-heptanedionate): a structurally well-defined O-containing transition metal complex is reported as an efficient catalyst for Suzuki, Heck, and Sonogashira cross-coupling reactions. The protocol was also applied successfully for cyanation of aryl halides under milder operating conditions. The system tolerated the coupling of various aryl halides with alkenes, alkynes, and organoboronic acid along with the cyanation of aryl halides providing good to excellent yields of desired products.     

Boehmite@tryptophan‐Pd nanoparticles: A new catalyst for C–C bond formation

A boehmite@tryptophan‐Pd nanoparticulate catalyst was prepared by a simple, fast and convenient route. The nanomaterial was characterized using various techniques and employed as a thermally stable catalyst for Heck, Stille and Suzuki cross‐coupling reactions. Optimized conditions for these reactions are described. The catalyst could be isolated, post‐reaction, by simple filtration and recycled for several consecutive cycles without a notable change in its activity.     

温度和时间对有机合成反应影响的探讨

根据物理化学和有机合成原理,从动力学、热力学、反应机理及溶解度等各方面详细分析了反应温度和反应时间对有机合成反应的影响。通过这些分析,可以让同学们更好地在合成反应课程的学习中掌握和分析反应温度和反应时间对反应的影响。     

Oxa-Michael加成反应的研究新进展

Oxa-Michael加成反应是一类重要的反应, 经常被用于天然产物的合成, 但该反应直到近几年才被深入研究. 简要综述了oxa-Michael加成反应的研究进展.     

Tandem Hass-Bender/Henry reaction for the synthesis of dimethylnitro alcohols from benzylic halides

Dimethylnitro alcohols are constructed in a one-pot process from benzylic halides and 2-nitropropane. The use of tetrabutylammonium fluoride (TBAF) as the promoter is essential for this tandem Hass-Bender/Henry reaction to proceed.     

钯催化的交叉偶联反应——2010年诺贝尔化学奖获奖工作介绍

钯催化的交叉偶联反应是非常实用的合成新方法.文章给出了Heck反应、Negishi反应和Suzuki反应的概念,对其反应机理作了详细的说明,并对其在复杂化合物和天然产物全合成中的应用作了评价.     

具有相同简单级数的不同反应类型的半衰期公式

化学反应的半衰期公式不仅与反应级数有关,而且与反应类型相关。具有相同简单级数的不同类型反应的半衰期表达式也往往不一致。对具有简单级数反应的半衰期表达式进行了分析,重点讨论了不同类型的二级反应和三级反应半衰期表达式的特点及其他们之间的内在联系和区别。