乙酰二茂铁缩烟酰肼的合成及其晶体结构

烟酸乙酯与肼反应得烟酰肼(2);2与乙酰二茂铁反应合成了一种新型的含二茂铁基Schiff碱——乙酰二茂铁缩烟酰肼(1),其结构经1H NMR,IR,元素分析和XRD表征。1属四方晶系,空间群I-4,晶胞参数a=21.746 6(18),b=21.746 6(18),c=7.007 5(12),V=3 314.0(7)3,Z=8,Dc=1.436 g·cm-3,R1=0.084 9,wR2=0.247 2。1通过分子内和分子间C-H┈N氢键使相邻的四个分子彼此连接形成环状结构。     

新型二茂铁三氮唑类Schiff碱的合成、晶体结构及其电化学性质

以乙酰二茂铁和氨基三氮唑为原料,合成了两种新型的二茂铁三氮唑Sch iff碱化合物,其结构通过IR,1H-NMR,元素分析和X-射线单晶衍射法确定。X射线单晶结构分析表明,固态时化合物1 a与一分子水通过分子间氢键形成-维无限链状结构,其晶体属单斜晶系,P21/n空间群,M r:312.16,a=11.679(2),b=9.862(2),c=12.717(3),β=108.60(3)0k,v=1388.3(5),Z=4,D c=1.493mg.m-3,μ=0.71073,F(000)=648,最终偏离因子R=0.0454,wR=0.0984。电化学分析表明1 a和1b的电化学性质相似,在电位0.4~1.1V范围内,都只有一对氧化-还原峰,对应于Fc/Fc 电对,且该过程是受扩散控制的可逆过程。     

[Hg(C5H4S5)I2]2的合成与晶体结构(C5H4S5 = 4,5-亚乙基二硫杂-1,3-二硫杂-2-硫酮)

用 HgI2 和 4,5-亚乙基二硫杂-1,3-二硫杂-2-硫酮 (C5H4S5)反应,合成一种二核汞配合物[Hg(C5H4S5)I2]2 1。X 射线衍射结果表明,晶体属于单斜晶系,C2/c 空间群,晶胞参数 a =21.6847(1),b = 8.5125(4),c = 15.6699(8),a=112.7850(1)°,V=2666.8(2) ?3。Mr = 1357.54,Z = 4,Dx = 3.381 g/cm3,ì = 16.913 cm–1,F(000) = 2400,R=0.0639,wR=0.1711,S=1.052。配合物 1 具有二聚体结构,2 个汞原子通过 2 个碘原子桥联,形成 1 个 Hg2I2菱形平面,汞原子周围的配位是四面体结构,通过分子间的硫…硫作用和碘…硫作用,形成准二维超分子网络。 S S S H g I I S S S S I I H g S     

五元杂环spacer结构调控的分子内电荷交互作用

研究五元杂环(spacer)桥对分子内电荷传递调控规律是开发功能分子材料的基础。本文通过环合反应制备了9个2,5-双二茂铁基五元杂环衍生物,包括: 2,5-双二茂铁基-1-苯基-吡咯(1),2,5-双二茂铁基呋喃(2),2,5-双二茂铁基噻吩(3),2,5-双二茂铁基-1H-咪唑(4),2,5-双二茂铁基噁唑(5),2,5-双二茂铁基噻唑(6),2,5-双二茂铁基-1H-1,3,4-三氮唑(7),2,5-双二茂铁基-1,3,4-噁二唑(8)和2,5-双二茂铁基-1,3,4-噻二唑(9)作为模型分子。通过元素分析,傅里叶变换红外(FTIR)光谱,质谱(MS)和核磁共振(NMR)等手段对化合物结构进行了表征,采用循环伏安电化学(CV)和密度泛函(DFT)量化模拟计算研究了分子内电荷传递与五元杂环(spacer)结构间的调控关系,发现化合物(1-9)二茂铁间电荷交互作用随着spacer中杂原子数量的增加而减小,分子内电荷选择短程杂原子桥作为传输通道,spacer结构对二茂铁间电荷传递发挥着重要的调控作用。     

氨基化合物与乙酰二茂铁环汞的反应

对甲基苯胺、氨基吡啶、乙二胺、氨基硫脲等与乙酰二茂铁环汞反应合成了一系列乙酰二茂铁亚胺和乙酰二茂铁亚胺环汞,其结构经1HNMR, IR和元素分析表征。其中[η5 - C5H4MeCNNHC(S)NH2 ]Fe(η5 - C5H5 )·1 /2CH2Cl2 经X 射线单晶衍射仪确证属三斜晶系,P- 1空间群,Mr=387. 12, a=7. 5939(2) , b=7. 8355(2) , c=14. 822(3) , α=92. 72(3)°, β=100. 62(3)°, γ=101. 92°, V=848. 2(3) 3, Z=2, ρC=2. 049mg·cm-3, μ=1. 323mm-1, F(000) =398,最终偏离因子R=0. 0537, wR=0. 1283。     

双二茂铁甲氨基异丙醇的合成与晶体结构

双二茂铁甲醇与BF3在CH2Cl2中与BF3作用形成的双二茂铁甲基碳正离子, 无需从溶液中分离出来, 便可直接与异丙醇胺反应得到双二茂铁甲氨基异丙醇,且产率较高。由乙醇重结晶得到的单晶经X射线衍射法测试表明, 该化合物晶体属三斜晶系, P空间群, 化学式为2[C24H27Fe2NO]CH3CH2OH, Mr = 960.40。晶胞参数: a = 10.6825(7), b = 14.463(1), c = 15.794(1) , ?= 69.593(1), b = 75.535(1), g = 81.302(1)? V = 2208.9(3) 3, Z = 2, Dc = 1.444 g/cm3, m(MoKa) = 1.332 mm-1, F(000) = 1004, 对于I > 2(I)的4742个衍射点, 最终的R = 0.0525、wR = 0.0704。晶体结构由2分子双二茂铁甲氨基异丙醇和1分子乙醇通过氢键缔合组成。     

微波辐射下2,6-二甲基-3,5-二乙氧羰基-4-二茂铁基-1,4-二氢吡啶的合成和晶体结构

标题化合物C_23H_27FeNO_4是由二茂铁甲醛、乙酰乙酸乙酯、尿素负载于SiO2在微波辐射下干反应而得。用元素分析、IR、1H NMR对化合物进行了表征,并通过了单晶X-射线衍射法确定了晶体结构,其晶体属三斜晶系,空间群P,Mr = 437.32,a = 7.462(2),b = 8.3574(13),c = 16.491(3) , a = 78.36(2),b = 88.76(3),g = 86.11(2),V = 1004.9(3) 3,Z = 2,Dc = 1.445 g/cm3,m(MoKa) = 7.80 cm-1,F(000) = 460.00,最终的偏离因子为R = 0.063,wR = 0.180。该化合物是1个由二茂铁基和1,4-二氢吡啶环组成的双功能团化合物,其中吡啶环为船式结构。     

某些有机锡二茂铁和有机胂二茂铁衍生物的合成、表征及晶体结构

N,N-二甲基氨甲基二茂铁的单锂化物与三苄基氯化锡反应,得到1-二甲氨甲基-2-三苄基锡二茂铁(Ⅰ);与二苄基二氯化锡反应,得到二苄基二[2-(二甲氨甲基)二茂铁基]锡(Ⅱ).1-二甲氨甲基-2-(二苯胂基)二茂铁经单锂化后,再与二苯基氯化胂反应,生成1-二甲氨甲基-2,5-二(二苯胂基)二茂铁(Ⅲ);在四甲基乙二胺存在下,1-二甲氨甲基-2-(二苯胂基)二茂铁经双锂化后,再与二苯基氯化胂反应,得到1-二甲氨甲基-2,5,1'-三(二苯胂基)二茂铁(Ⅵ).化合物-经元素分析和¹HNMR表征,还用X射线衍射测定了化合物的晶体结构.化合物晶体为三斜晶系,空间群P1,a=1.0548(2)nm,b=1.3622(3)nm,c=1.5846(3)nm,α=95.87(3)°,β=96.54(3)°,γ=107.67(3)°,Z=2.     

新型1,1′-双(4,5-二烷基)咪唑二茂铁的合成及其晶体结构

1,1′-二茂铁二甲醛与烷基二酮反应合成了3种新型的1,1′-双(4,5-二烷基咪唑)二茂铁,其结构经1HNMR,13C NMR,IR,ESI-MS及元素分析表征。1,1′-双(4,5-二苯基咪唑)二茂铁醋酸盐(1a′)的晶体结构经X-射线单晶衍射表征。1a′的晶体结构显示二茂铁的两个取代咪唑通过与醋酸的氢键作用形成顺式构型,探讨了顺式构型与反式构型的转化条件。1a′属单钭晶系,C2/c空间群,晶胞参数:a=15.832(4),b=19.255(4),c=14.781(4),β=121.837(3)°,V=3828.0(15)3,Z=4,F(000)=1 687,Dc=1.395 g.cm-3,Mr=804.07。     

meso和dl 2,3-二氰基-2,3-二(p-取代苯基)丁二酸二乙酯的~1H NMR研究

测定了meso和dl 2,3-二氰基-2,3-二(p-X苯基)丁二酸二乙酯(X=OCH_3,CH_3,H,Cl,NO_2)的~1H NMR谱及X为CH_3相应二乙酯的~1H Noesy谱。在meso和dl异构体中,苯环m-~1H的化学位移与p-X的Hammett基团常数σ呈线性关系,c~1H的化学位移仅受分子构型的影响,;△δdl-meso为负值,乙氧基中CH_2和CH_3的质子化学位移也只受分子构型的影响,△δdl-meso均为正值。     

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%.     

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.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.