三苯基锡2－噻吩甲酸酯的合成、性质和晶体结构

用三苯基氯化锡与2-噻吩甲酸钠反应，合成了三苯基锡2-噻吩甲酸酯，并进行 了红外光谱、核磁共振氢谱及质谱表征。X射线单晶衍射表明，化合物属单斜晶系 ，空间群P21/n，晶胞参数：a=1.3429(7)nm，b=1.11773(6)nm，c=1.4241(8)nmβ =116.519(6)°，V=2.0146(18)nm^3,Z=4，Dc=1.573g/cm^3，R1=0.0391，Wr2=0. 0943。该化合物的晶体是由孤立的分子所组成，四配位的锡原子呈畸变的四面体构 型，配体噻吩环上的硫原子和锡原子之间存在弱的配位作用。     

一苄基锡三（2－吡啶甲酸酯）的合成和晶体结构

利用三苄基氯化锡和2－吡啶甲酸在三乙胺存在下以1：摩尔比反应，合成了非 预期的去苄基化产物一苄基锡三（2－吡啶甲酸酯）。通过元素分析、红外光谱、 核磁共振氢谱和X射线单晶衍射对其结构进行了表征。测试结果表明：该化合物为 单斜晶系，空间群P21，a=1.3141(2)nm,b=1.13127(17)nm,c=1.7122(3)nm,β-110. 581(2°），Z=4,V=2.3829(6)nm^3,Dc=1.606g/cm^3,μ=1.118mm^-1,F(000)=1152, R1=0.0397,wR2=0.0881。该化合物为单体结构，锡原子呈七配位畸变五角双锥构型 。     

三苄基和三丁基锡4-吡啶甲酸酯聚合物的合成、性质及晶体结构

用三苄基氯化锡及三丁基氯化锡与4-吡啶甲酸钠反应,分别合成了三苄基锡4-吡啶甲酸酯(1)和三丁基锡-4-吡啶甲酸酯(2),并进行了红外光谱、核磁共振氢谱及质谱表征.X射线单晶衍射分析结果表明,化合物1属单斜晶系,P2₁/n空间群,晶胞参数:a=0.96564(8)nm,b=1.64085(14)nm,c=1.49403(13)nm,β=97.681(2)₀,V=2.3460(3)nm₃,Z=4,D_c=1.456g/cm³.化合物2属单斜晶系,P2₁/n空间群,晶胞参数:a=0.96673(14)nm,b=2.3845(4)nm,c=0.97071(14)nm,β=112.463(3)o,V=2.0679(5)nm₃,Z=4,D_c=1.324g/cm³.两个化合物均通过4-吡啶甲酸配体的氮原子桥联,形成五配位三角双锥构型的一维无限链聚合物.     

三苯基锡硫代苯甲酸酯的合成、性质和晶体结构

用三苯基氯化锡与硫代苯甲酸在三乙胺存在下反应，合成了三苯基锡硫代苯甲 酸酯，并进行了红外光谱及核磁共振氢谱表征。X射线单晶衍射表明，化合物属正 交晶系，空间群P2_12_12_1，晶胞参数：a = 0.8306(3) nm, b = 1.6906(5) nm, c = 3.1459(10)) nm, V = 4.417(2) nm~3, Z = 8, D_c = 1.465 g/cm~3, R_1 = 0.0472, wR_2 = 0.1012。该化合物的晶体是由孤立的分子所组成，四配位的锡 原子呈畸变的四面体构型，配体羧基上的氧原子和锡原子之间存在弱的配位作用。     

三苯基锡-2-(1，2-亚乙二硫)亚甲基-3-羰基-5-芳基-4-戊烯酸酯的合成及晶体结构

由2-(1,2-亚乙二硫)亚甲基-3-羰基-5-芳基-4-戊烯酸与三苯基氢氧化锡反应,合成了九个标题化合物3。用X射线衍射法测定了3b的晶体结构。该晶体属三斜晶系,空间群P1,a=0.9074(2)nm,b=1.6809(3)nm,c=2.1834(4)nm,α=77.57(3)ⅲ,β=88.04(3)ⅲ,γ=89.47(3)ⅲ,V=3.2503nm^3,Z=2;R=0.0592。由锡氧原子间距离可推测,该晶体中羧酸根作为双齿配体与锡原子形成了分子内五配位结构。     

三苯基锡-2-(1, 2-亚乙二硫)亚甲基-3-羰基-5-芳基-4-戊烯酸 酯的合成及晶体 结构

由2-(1,2-亚乙二硫)亚甲基-3-羰基-5-芳基-4-戊烯酸与三苯基氢氧化锡反应,合成了九个标题化合物3。用X射线衍射法测定了3b的晶体结构。该晶体属三斜晶系,空间群P1,a=0.9074(2)nm,b=1.6809(3)nm,c=2.1834(4)nm,α=77.57(3)ⅲ,β=88.04(3)ⅲ,γ=89.47(3)ⅲ,V=3.2503nm^3,Z=2;R=0.0592。由锡氧原子间距离可推测,该晶体中羧酸根作为双齿配体与锡原子形成了分子内五配位结构。     

原位脱羧制备的配合物(HP2W18O62)(C6H6NO2)5·2H2O:结构、光谱及电化学性能

采用水热法将钨酸钠和浓磷酸与有机配体吡啶-2,6-二羧酸通过原位脱羧制得配合物(HP2W18O62)(C6H6NO2)5.2H2O(1),并用红外光谱、紫外光谱、循环伏安(CV)和X射线单晶衍射等方法进行了表征。分子中的2-吡啶甲酸来源于吡啶-2,6-二羧酸的脱羧反应。化合物1属于单斜晶系,空间群P21/n,晶胞参数分别为:a=1.553 3(2)nm,b=2.006 3(3)nm,c=2.759 9(4)nm,β=103.981(2)°,Z=4,F(000)=8 816。分子间氢键和2-吡啶甲酸与杂多化合物间的弱相互作用使该化合物具有3D超分子结构。CV结果表明,化合物1有四步氧化还原反应。     

三维骨架结构有机锡化合物－－1，5－戊二酸双（三苯基锡）酯的合成、谱学表征和晶体结构

用三苯基氯化锡与1，5－戊二酸二钠以2：1摩尔比反应，合成了1，5－戊二酸 双（三苯基锡）酯，并进行了红外光谱、核磁共振氢谱及质谱表征。X射线单晶衍 射表明，该化合物属正交晶系，空间群C222（1），晶胞参数：a=1.5075(5)nm， b=4.8021(17)nm,c=2.8944(9)nm,α＝90°,β=90°，γ＝90°，V＝20.953(12) nm^3，Z=8,Dc=1.316g/cm^3，μ＝1.226mm^-1,F(000)=8280,R1=0.0546,wR2=0. 1182。晶体结构中存在5种化学环境不同的三角双锥构型的锡原子，由于配体中两 个羧基在不同方向的交联作用，使化合物呈现三维骨架结构，并且在骨架结构中存 在沿a轴和c轴方向伸展的规则的大环直孔道。     

三苄基锡哌啶氨荒酸酯和二苄基锡双哌啶氨荒酸酯合成及晶体结构

利用三苄基氯化锡，二苄基二氯化锡和哌啶氨荒酸钠反应，合成了三苄基锡哌 啶氨荒酸酯（1）和二苄基锡双哌啶氨荒酸酯（2）。通过元素分析、红外光谱、核 磁共振氢谱和质谱对其结构进行了表征。用X-射线单晶衍射测定了这两个化合物的 晶体结构。化合物1为三斜晶系，空间群P-1，a=1.0271(2)nm,b=1.1131(2)nm,c=1. 2096(2)nm,α=75.56(3)°，β=81.09(3)°，γ=89.81(3)°，Z=2。化合物2为单 斜晶系，空间群P21/c,a=0.9710(3),b=2.436(1),c=1.2393(3)nm,β=90.28(2)°， Z=4。在1的晶体中， 锡原子呈五配位畸变三角双锥构型；2的晶体则是六配位的畸 变八面体构型。     

氧化-4-吡啶甲酸桥联的一维链状三丁基锡配合物的合成与晶体结构

利用双三丁基氧化锡与氧化-4-吡啶甲酸(HOCOC5H4NO)以物质的量比1∶2反应,合成了有机锡配合物[Bu3Sn(OCOC5H4NO)]n。通过元素分析、红外光谱和核磁共振氢谱对其结构进行了表征,用X射线单晶衍射测定了它的晶体结构。结果表明,该配合物晶体属单斜晶系,空间群为C2/c,晶胞参数a=2.002 8(9)nm,b=1.224 7(6)nm,c=1.913 6(12)nm,β=119.145(6)°,Z=8,V=4.166(4)nm3,Dc=1.365 g.cm-3,μ=1.239 mm-1,F(000)=1 760,R=0.052 9,wR=0.192 1,GOF=1.013。在配合物中锡原子由氧化-4-吡啶甲酸桥联为五配位的畸变的三角双锥构型。氧化-4-吡啶甲酸配体中N-O基团中的氧原子和另一配体中的羧基氧原子与中心锡原子配位,形成无限一维链状有机锡配合物。该配合物具有良好的热稳定性和较高的抗肿瘤活性。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.