三聚氰胺和对苯二氧乙酸共晶中的三维氢键网络

合成了一个新的超分子聚合物{(MAH+)2(p-BDOA2-)·4H2O}n(MA=三聚氰胺;p-BDOAH2=对苯二氧乙酸),通过X-射线对其结构进行了表征。在该聚合物中,三聚氰胺被质子化,相邻的三聚氰胺分子通过氢键形成一维阳离子链(MAH+)n,相邻的阳离子链由p-BDOA2-阴离子连接构成波浪状的二维层,层状结构通过水分子的氢键和π-π堆积形成三维结构。     

三聚氰胺和对苯二氧乙酸共晶中的三维氢键网络(英文)

合成了一个新的超分子聚合物{(MAH+)2(p-BDOA2-)·4H2O}n(MA=三聚氰胺;p-BDOAH2=对苯二氧乙酸),通过X-射线对其结构进行了表征。在该聚合物中,三聚氰胺被质子化,相邻的三聚氰胺分子通过氢键形成一维阳离子链(MAH+)n,相邻的阳离子链由p-BDOA2-阴离子连接构成波浪状的二维层,层状结构通过水分子的氢键和π-π堆积形成三维结构。     

邻菲啰啉衍生物配体和柔性二羧酸共同构筑的钴(Ⅱ)配位聚合物

通过水热方法合成了一个新的化合物[Co2(L)2(1,5-PDC)2].0.5H2O(L为邻菲啰啉衍生物2-(2-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline,1,5-PDC为庚二羧酸阴离子),并对该化合物进行了元素分析、红外和X射线单晶衍射表征。该化合物属于三斜晶系,空间群P1,晶胞参数C104H86Co4F4N16O17,a=1.108 2(5)nm,b=1.390 2(4)nm,c=1.601 7(6)nm,α=90.806(5)°,β=93.429(3)°,γ=111.312(5)°,V=2.293 0(15)nm3,Z=1,R=0.059 7,wR=0.160 8。在该化合物中,1,5-PDC阴离子桥联着相邻的钴离子从而形成了一维链状结构。存在于相邻链之间的π-π相互作用使一维链形成了二维超分子结构。此外,N-H…O和O-H…N氢键进一步地稳定了此二维超分子结构。     

基于萘基块新型开链冠醚的合成及晶体结构研究

以3,6-二溴-2,7-二羟基萘为起始原料,经与2-溴-N-苯基乙酰胺醚化,再用硼氢化钠和三氟化硼乙醚还原得基于萘基块新型的开链冠醚,两步总收率为96%.利用单晶X衍射研究其结构,晶体为三斜晶系,P-1空间群,a=9.588(3),b=10.898(3),c=13.060(4),α=103.190(4)°,β=93.953(4)°,γ=115.622(5)°,V=1176.0(6)3,Z=2,Dc=1.571 g/cm3,λ=0.71075 nm,μ(Mo Kα)=3.472 mm-1,Mr=353.22,F(000)=560.在晶体结构中,分子中的一个N—H基团与另外一分子形成双分叉氢键N—H…Br和N—H…O,进而组装成二聚体.这些中心对称的二聚体进一步通过C—H…π相互作用叠加成二维层状结构平行于(110)面.     

香豆素衍生物的合成及结构表征

合成了11个香豆素衍生物,产率53%—79%,利用元素分析、MS和¹HNMR对其结构进行了表征.同时,由2-氨基苯并噻唑(ABT)和8-甲氧基香豆素-3-甲酸乙酯(MCC)合成了给体-受体加合物ABT-MCC,通过X射线单晶衍射法测定了其晶体结构,晶体属三斜晶系,P1空间群,晶胞参数为:a=9.5978(19)Å,b=10.686(2)Å,c=10.693(2)Å,α=71.30(3)°,β=70.43(3)°,γ=88.99(3)°,V=973.9(3)ų,Z=2,D_x=1.359 mg/m³,μ=0.200 mm^-1,F(000)=416,R=0.0463,wR=0.0992.结果表明,在ABT-MCC晶体中,分子间通过N—H…N和N—H…O氢键作用形成对称的A…D…D′…A′氢键四聚体,并通过弱的C—H…O氢键连接成为一维超分子链状结构,进而分子间通过π-π堆积作用形成层状结构.     

锌配合物Zn(phen)(H2O)(3-mba)2的合成、结构表征及荧光性质

常温下,溶液法合成了一个单核结构的锌配合物Zn (phen)(H2O)(3-mba)2(phen:邻菲咯啉;3-Hmba∶3-甲基苯甲酸),并用红外光谱、元素分析、热重分析以及X射线单晶衍射表征了其结构.结果表明,配合物属于三斜晶系,空间群P1,晶胞参数:a=10.893(2)(A),b=11.461(2)(A),c=11.505(2)(A),α=95.54(3)°,β=115.80(3)°,γ =100.25(3)°,V=1247.9(4) (A)3,C28H24N2O5Zn,Mr=533.86,Z =2,Dc=1.421 g·cm-3,F(000) =552,最终偏离因子[I≥2σ(I)]R1=0.0471,wR2 =0.0954.在配位物分子中,中心锌离子是五配位模式,双分子间先通过O—H…O氢键形成二聚体,继而二聚体间通过相邻分子中的邻菲咯啉芳环的π-π堆积作用沿着a方向形成了一维超分子链.对配合物的荧光性能进行了测试.CCDC 1023439.     

1-苯甲酰基-3-(4,6-二甲氧基嘧啶-2-氨基)硫脲的合成、晶体结构及生物活性

以2-氨基-4,6-二甲氧基嘧啶、硫氰酸钾和苯甲酰氯为原料,在乙酸乙酯中合成了1-苯甲酰基-3-(4,6-二甲氧基嘧啶-2-氨基)硫脲,并用X射线单晶衍射法测定其晶体结构。结果表明,每个结构单元中有4个分子,该化合物属于三斜系,P1空间群,a=0.9040(2)nm,b=1.8285(4)nm,c=1.8931(5)nm,α=70.217(4)°,β=80.583(4)°,γ=84.110(4)°,V=2901.3(12)3,Dc=1.458g/cm3,μ=0.242mm-1,F(000)=1328,Z=8,R=0.0637,由2095个可观测衍射点[FO>4sig(FO)]得到的wR=0.1698。同层中相邻分子间的分子间氢键N—H…S(DA)和C—H…O(DA)的交叉作用以及层与层之间弱的π…π堆积作用使得化合物形成网状超分子结构。该结构的化合物具有良好的生物活性。     

吡啶-2，3，5，6-四甲酸双核锰(Ⅱ)配合物的合成及结构

合成了一个双核锰配合物[Mn2(H2pdtc)2(H2O)6].2H2O(H4pdtc=吡啶-2,3,5,6-四甲酸),并利用红外光谱、元素分析、X-射线单晶衍射分析及磁性分析等手段对其进行了表征及研究。该配合物为三斜晶系,P1空间群,晶胞参数a=0.84166(13)nm,b=0.933 75(14)nm,c=1.024 29(16)nm,α=111.248(2)°,β=90.733(2)°,γ=115.161(2)°,V=0.665 66(18)nm3,Z=1。结构分析表明,该配合物有一个双核单元,且该双核单元通过分子间氢键及π…π堆积作用形成三维超分子网状结构。     

锌配合物Zn(phen)(H_2O)(3-mba)_2的合成、结构表征及荧光性质（英文）

常温下,溶液法合成了一个单核结构的锌配合物Zn(phen)(H2O)(3-mba)2(phen:邻菲咯啉;3-Hmba:3-甲基苯甲酸),并用红外光谱、元素分析、热重分析以及X射线单晶衍射表征了其结构。结果表明,配合物属于三斜晶系,空间群P 1,晶胞参数:a=10.893(2)A,b=11.461(2)A,c=11.505(2)A,α=95.54(3)°,β=115.80(3)°,γ=100.25(3)°,V=1247.9(4)A3,C28H24N2O5Zn,Mr=533.86,Z=2,Dc=1.421 g·cm-3,F(000)=552,最终偏离因子[I≥2σ(I)]R1=0.0471,wR2=0.0954。在配位物分子中,中心锌离子是五配位模式,双分子间先通过O—H…O氢键形成二聚体,继而二聚体间通过相邻分子中的邻菲咯啉芳环的π-π堆积作用沿着a方向形成了一维超分子链。对配合物的荧光性能进行了测试。CCDC 1023439。     

配合物[Cd（1,3-BDC）（L）（H2O）2]·H2O的水热合成、晶体结构和荧光性质

利用水热方法制备了一个新的过渡金属镉配合物[Cd(1,3-BDC)(L)(H2O)2]·H2O(1,3-H2BDC=间苯二甲酸,L=2-(3-吡啶基)-1H-苯并咪唑),并通过元素分析、红外光谱和X-射线单晶衍射方法确定了该配合物的晶体结构.结构分析表明该配合物属于单斜晶系,P21/c空间群,晶胞参数a=1.016 41(6)nm,b=2.088 42(12)nm,c=1.001 38(6)nm,β=106.336 0(10)°,V=2.039 8(2)nm3,Z=4,R1=0.020 7,wR2=0.494.配合物中CdⅡ离子与L配体的1个吡啶N原子、1,3-BDC的4个氧原子和2个配位水的O原子配位,形成七配位的扭曲十面体结构.配体1,3-BDC的桥连相邻的CdⅡ离子形成一维聚合物链,相邻链间通过氢键和π…π作用形成三维超分子网络,并对该配合物的热稳定性和荧光性质进行了研究.     

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.