1-苯基-5-芳基-1,2-二氢-1,2,4-三唑-3-硫酮的合成

将取代苯甲酰氯1a～1f与硫氰酸钾反应, 得到的中间体不需纯化直接与苯肼反应, 成功地合成了1-苯基-5-芳 基-1,2-二氢-1,2,4-三唑-3-硫酮(2a～2f). 化合物2的结构通过红外光谱、核磁共振光谱和高分辨质谱进行了表征.     

3-甲基-9-芳基-1,8-二氧代-2,10-二氧杂蒽衍生物的合成

以芳醛、4-羟基-6-甲基-2-吡喃酮和1,3-环己二酮为原料,乙二醇为溶剂合成了一系列3-甲基-9-芳基-1,8-二氧代-2,10-二氧杂蒽衍生物.该反应产率高(70%～83%)、操作简单、后处理方便.产物的结构经红外光谱、核磁共振谱及单晶X射线衍射法表征.     

三组分一锅法合成1-羧甲基-6-芳基-1,2,3,4,5,6-六氢茚并[2,3-b]-喹啉-5,11-二酮

以芳醛、1,3-茚二酮、烯胺酮为原料, 冰醋酸为溶剂, 三组分一锅法合成了一系列茚并[2,3-b]喹啉类化合物. 该反应产率高(83%～93%)、操作简单、后处理方便. 产物的结构通过红外光谱、核磁共振谱和元素分析证实, 同时给出了该反应可能的反应机理.     

二醋酸碘苯促进苯并咪唑类化合物的合成

二醋酸碘苯促进下, 由邻苯二胺或4-甲基邻苯二胺与各种芳醛通过一步反应合成了13种苯并咪唑类化合物, 反应时间3～5 min, 反应产率83%～98%, 用核磁共振、红外光谱、质谱和元素分析对产物的结构进行了表征. 该合成方法具有底物适用范围广、反应条件温和、反应速度快、反应产率高的优点. 根据实验结果对该反应提出了可能的反应机理.     

N-(1, 3, 4-噻二唑-2-基)-N′-芳酰基脲的合成及其生物活性

2-氨基噻二唑与芳酰基异氰酸酯反应合成了13种N-(1,3,4-噻二唑-2基)-N'-的芳酰基脲,产率为54.5%～86.2%. 用核磁共振氢谱、红外光谱和元素分析确证了目标化合物的结构,室内的生物活性测定试验表明,目标化合物中的2b、2c、2e和2h具有优良的植物生长调节活性.     

咪唑盐二醋酸碘苯促进苯并咪唑类衍生物的水相合成

报道了一种简便高效的苯并咪唑类衍生物的水相合成新方法, 合成了兼具离子液体和二醋酸碘苯双重特点的咪唑盐二醋酸碘苯. 以水为溶剂, 在咪唑盐二醋酸碘苯促进下, 通过邻苯二胺或4-甲基邻苯二胺与各种芳醛室温氧化环合, 一步合成了13种苯并咪唑类衍生物, 反应时间25～45 min, 反应产率92％～98％. 用核磁共振、红外光谱、质谱和元素分析对产物的结构进行了表征, 提出了可能的反应机理. 该合成方法具有底物适用范围广、反应条件温和、反应速度快、反应产率高及氧化剂对应的还原产物可回收利用等优点, 是一种环境友好的绿色合成方法.     

二(β-二亚胺基)二价稀土配合物催化醛/酮与亚磷酸二乙酯的氢磷化反应

研究了一系列二(β-二亚胺基)二价稀土配合物[Eu(L~(2,6-ipr2))_2·CH_3C_6H_5,L~(2,6-ipr2)=[N(2,6-~(i)Pr_2C_6H_3)C(Me)]_2CH~-(1);Eu(L~(2,6-Me2))_2(THF),L~(2,6-Me2)=[N(2,6-Me_2C_6H_3)C(Me)]_2CH~-(2);Eu(L~(2,4,6-Me3))_2(THF),L~(2,4,6-Me3)=[N(2,4,6-Me_3C_6H_2)-C(Me)]_2CH~-(3);Eu(L~(2,6-ipr2)Ph)2,L~(2,6-ipr2)Ph=[(2,6-iPr_2C_6H3_)NC(Me)CHC(Me)N(C_6H_5)]–(4);Sm(L~(2,6-ipr2))_2·CH_3C_6H_5(5);Yb(L~(2,6-ipr2)Ph)2(6);Yb(L~(2-Me))2(THF),L~(2-Me)=[N(2-Me C6H4)C(Me)]2CH–(7)]对醛/酮与亚磷酸二乙酯的氢磷化反应的催化行为.发现所有配合物都可以在温和条件下,高效地催化芳醛以及杂环芳醛与亚磷酸二乙酯的氢磷化反应,在催化剂用量为0.08 mol%,25℃,无溶剂条件下反应5 min,α-羟基膦酸酯的收率可以达到90%~99%.催化活性有赖于β-二亚胺基的结构,其活性顺序为L~(2,6-Me2)L~(2,4,6-Me3)L~(2,6-ipr2)≈L~(2,6-ipr2)Ph.该催化体系具有优秀的醛底物适应能力.这类二价稀土配合物也可以有效地催化未活化的酮与亚磷酸二乙酯的反应,并显示良好的底物适应能力.     

含吡咯基亚胺配体稀土铕配合物催化合成胍

以2-(2,4,6-Me3C6H2N=CH)C4H3NH为配体与铕配合物[(Me3Si)2N]3Eu(μ-Cl)Li(THF)3反应,合成了三价铕金属配合物[2-(2,4,6-Me3C6H2N=CH)C4H3N]3Eu(THF),以此配合物为催化剂催化芳胺与N,N’-二异丙基碳二亚胺反应,得到一系列胍产物,研究了反应时间、温度、催化剂用量和溶剂对催化反应的影响。结果表明:铕配合物具有良好的催化活性,以2%mol的催化剂用量、在THF中加热60℃反应8 h,得到高于80%产率的相应胍产物。     

三组分一锅法合成3-甲基-1-苯基-4-芳基-4,11-二氢-4H-吡唑并[4’,5’∶3,2]吡啶并[5,6-c]香豆素

以芳醛、4-羟基香豆素和3-甲基-1-苯基-5-氨基吡唑为原料,用少量冰醋酸作溶剂,三组分一锅法合成一系列吡唑并[4′,5′∶3,2]吡啶并[5,6-c]香豆素衍生物,该反应产率高(79％～94％)、操作简单、后处理方便.产物的结构经红外光谱、核磁共振氢谱、元素分析及单晶X射线分析证实.     

二茂铁-肽Fc-Gly-Pro-Arg(NO_2)-OMe的合成及其与Cu(Ⅱ)作用

以二茂铁甲酸、甘氨酸(H-Gly-OMe)、脯氨酸(Boc-Pro-OH)、精氨酸(H-Arg(NO2)-OMe)等为原料,苯并三唑-1-四甲基六磷酸酯(HBTU)和1-羟基苯并三唑(HOBT)为缩合剂,采用液相法合成了二茂铁-肽Fc-Gly-Pro-Arg(NO2)-OMe(简称Fc-GPR),其总收率为48.1%.并对目标产物进行了红外(IR)光谱、核磁共振氢谱(1H-NMR)、质谱(ESI-MS)等表征.通过电化学方法研究了目标产物与Cu(Ⅱ)之间的相互作用.结果表明:目标产物在溶液中的电化学行为表现为可逆氧化还原反应,氧化和还原峰电位分别为0.624和0.552V(vsAg/AgCl),氧化和还原峰电流之比Ipa/Ipc为1.13,电极反应过程为扩散控制.目标产物与Cu(Ⅱ)形成配位比为2∶1的配合物.Fc-GPR与Cu(Ⅱ)的电极反应过程符合电化学-化学-电化学(ECE)历程.     

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.     

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.     

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.     

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.     

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

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.     

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%).