Reaction of Lawesson's reagent with Mannich base hydrochlorides: synthesis of novel 4H-1,3,2-oxathiaphosphorine-2-sulfide derivatives

In a simple and general protocol, the treatment of Mannich base hydrochlorides, derived from acyclic and cyclic ketones, with Lawesson's reagent, leads to novel 4H-1,3,2-oxathiaphosphorine derivatives in good yields. A possible reaction mechanism, involving a [4+2] cycloaddition, is proposed.     

Synthesis and anti-bacterial activity of novel dihydrochromeno[8,7-e][1,3]oxazine-2(8H)-thiones

A novel series of sulfur-containing dihydrochromeno[8,7-e][1,3]oxazine-2(8H)-thiones has been synthesized through an eco-friendly Mannich-type condensation cyclization reaction of 7-hydroxy-4-methyl-2-thiocoumarin or 6-chloro-7-hydroxy-4-methyl-2-thiocoumarin with formaldehyde and primary amines in water at 80–90°C for 2 h. All the synthesized compounds were screened for their in vitro anti-bacterial efficacy against two Gram-positive and three Gram-negative bacterial strains by using the disc diffusion method. The compound (8c) was found to be most potent with the zone of inhibition of 16 and 15 mm against Staphylococcus aureus ATCC 2937 and Klebsiella pneumoniae ATCC 31488, respectively.     

2-十六烷基噻吩酮的合成工艺改进

2-烷基噻吩酮类化合物是合成2-烷基噻吩类化合物的重要化工中间体.研究了在无水氯化锌催化下十六烷基酰氯和噻吩在苯溶液中的傅-克反应,收率90.3%.溶剂可以循环使用,适合工业化生产.     

新试剂meso─四（3─溴─4─羟基─5─甲氧基苯基）卟啉的合成及其性质的研究

报道了新试剂ｍｅｓｏ－四（３－溴－４－羟基－５－甲氧基苯基）卟啉的合成方法，对试剂的理化性质、分析特性及其与金属离子的显色反应也作了研究，并提出了该试剂的应用前景。     

Regioselective synthesis of new 2,5,6-trisubstituted 5,6-dihydro-2H-pyrazolo[3,4-d]thiazoles from 5-dimethylaminoethylene-thaozolidin-4-thiones

Thiazolidin-4-ones assembled through one-pot three-component (carbonyl compound, amine and ethyl mercaptoacetate) reactions in the presence of dicyclohexyl carbodiimide, on simultaneous treatment with dimethyl formamide dimethylacetal and Lawesson's reagent furnished 5-dimethylaminomethylene thiazolidin-4-thiones. These thiones on condensation with hydrazine derivatives afforded 2,5,6-trisubstituted-5,6-dihydro-2H-pyrazolo[3,4-d]thiazoles 4 and not their possible 1,5,6-trisubstituted regioisomers 5. Results of single-crystal X-ray diffraction studies of thiazolidin-4-one 1b have been reported. The structures of all the synthesized compounds were established by spectral data. DFT studies on regioisomers were carried out using B3LYP with the 6-31G** basis set and carbon NMR shifts of 4 show good correlation with experimental values.     

5-（2-噻吩）-2-对-甲苯基噁唑的合成

以2-溴-1-（2-噻吩）-1-乙酮和对-甲基苯甲胺为原料,在复合催化剂碘与叔丁基过氧化氢的作用下,通过氧化环合反应合成了5-（2-噻吩）-2-对-甲苯基噁唑。产物结构经FTIR,NMR 和MS检测。结果显示：合成产物的最佳条件为：2-溴-1-（2-噻吩）-1-乙酮1 mmol、对-甲基苯甲胺1.3 mmol、碘0.2 mmol、质量分数55%的叔丁基过氧化氢1.2mmol、碳酸氢钠1.0 mmol,室温下反应12 h,产物收率为89.7 %。抑菌圈测定结果显示该产物对大肠杆菌具有强的抑菌能力。     

钯催化Suzuki偶联反应合成2-(3'-噻吩基)噻唑

以3-噻吩硼酸和2-溴噻唑为原料,以Pd(PPh3)4为催化剂,通过Suzuki偶联反应合成了2-(3'-噻吩基)噻唑,考察了不同的碱,不同的溶剂,不同原料比例和不同催化剂比例对该Suzuki偶联反应产率的影响.结果显示:目标产物收率在溶剂为乙醇,K2CO3为碱,原料比例为1.5:1的时候最高,且反应时间较短.     

2-（2-噻吩）乙胺合成工艺研究

研究了2-（2-噻吩）乙胺的合成工艺.噻吩甲醛与丙二酸经Knoevenagel-Doebner缩合生成3-（2-噻吩）丙烯酸,收率87%.3-（2-噻吩）丙烯酸与氯化亚砜和氨作用生成3-（2-噻吩）丙烯酰胺,收率91%;铜盐催化下用水合肼还原3-（2-噻吩）丙烯酰胺生成3-（2-噻吩）丙酰胺,收率99%;3-（2-噻吩）丙酰胺经Hoffman降解得2-（2-噻吩）乙胺,收率64%.由核磁共振氢谱、质谱和液谱对产物及中间体的结构和纯度进行了表征.     

氨基-3(2H)-哒嗪酮合成研究进展

以取代3（2H）-哒嗪酮为起始原料,根据反应试剂不同对其合成方法进行简要概述.     

Synthesis of 2,5-diaroyl-3-arylthiophenes: novel tandem reactions mediated 3+2-self annulation of bis(aroylmethyl) sulfides

A series of 2,5-diaroyl-3-arylthiophenes were obtained from the 3+2-self annulation of bis(aroylmethyl) sulfides in the presence of sodium hydroxide. This transformation occurs presumably via a tandem intermolecular condensation - ring closing intramolecular displacement-aromatization via air oxidation and elimination sequence.     

Role of 1,10‐phenanthroline and ortho phosphoric acid on graft polymerization of vinyl monomers from poly (vinyl alcohol) in the presence of Fenton's reagent

The effect and role of 1,10‐phenanthroline (o‐phen) and ortho phosphoric acid on graft polymerization of vinyl monomers from poly (vinyl alcohol) (PVA) in the presence of Fenton's reagent have been studied. Reaction conditions were optimized. Fourier transform infrared (FT‐IR) spectra were used for confirmation of grafting. A probable mechanism of grafting to elucidate the role of phenanthroline and phosphoric has been suggested. Thermal properties of the grafted polymer were studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2335–2339, 2005     

N-[4-(间甲基苯甲酰基哌嗪)乙酰基]-N-甲基-3-(1-萘氧基)-3-(2-噻吩基)-丙胺的合成

以N-甲基-3-(1-萘氧基)-3-(2-噻吩基)-丙胺(Duloxetine)为原料,合成了标题化合物.中间体和产物的结构经 ~1HNMR、IR和质谱表征.     

Synthesis and characterization of poly(N-(2-(thiophen-3-yl)methylcarbonyloxyethyl)maleimide) and its spectroelectrochemical properties

A new monomer; N-(2-(thiophen-3-yl)methylcarbonyloxyethyl) maleimide (NMT) was synthesized. The chemical structure of the monomer was characterized by Nuclear Magnetic Resonance (¹H-NMR) and Fourier Transform Infrared (FTIR) Spectroscopy. Electrochemical polymerization of NMT was performed in acetonitrile (AN)/borontrifloride ethylether (BFEE) solvent mixture (1:1, v/v) where tetrabutylammonium tetrafluoroborate (TBAFB) was utilized as the supporting electrolyte. The resulting conducting polymer was characterized by Fourier Transform Infrared (FTIR) Spectroscopy, thermal analyses and Scanning Electron Microscopy (SEM). Electrical conductivity was measured by the four-probe technique. The spectroelectrochemical behavior and switching ability of P(NMT) film were investigated by UV–Vis spectrophotometry. P(NMT) revealed color changes between yellow and blue in the reduced and oxidized states respectively.     

One-pot three-component synthesis of some novel ethyl 3-alkyl-2-thioxo-2,3-dihydrothiazole-4-carboxylates under solvent- and catalyst-free conditions at room temperature

A green and efficient one-pot three-component synthesis of some novel ethyl 3-alkyl-2-thioxo-2,3-dihydrothiazole-4-carboxylates from the reaction of primary alkyl or benzyl amines, carbon disulfide and ethyl bromopyruvate is introduced. This straightforward technique gave the looked-for products in high yields during 1.5–3?h without need for catalyst or solvent assistance.     

Synthesis, electropolymerization, and photoelectrochemical characterization of 2,7-di(thiophen-2-yl)-N-methylcarbazole

A new copolymer derived from 2,7-carbazole with thiophene is reported. This copolymer was obtained through the synthesis of 2,7-dibromo-N-methyl carbazole and 2-bromothiophene using a Kumada-type reaction to bond both rings and using two different kinds of Pd catalysts, [Pd(OAc)₂] and [Pd(PPh₃)₄], with significant differences in their yields. The trimer that was obtained was subsequently electropolymerized using cyclic voltammetry, and the photoelectrochemical properties were determined. Polymerization using electrochemistry showed that the trimer contains two types of possible bonds for the formation of the macromolecule, which led to the formation of two distinctly different materials. The obtained materials exhibit promising photoelectric responses suggesting that they both can be explored in the designing of photovoltaic cells.     

1-(芘-1-基)-3-(噻吩-3-基)丙烯酮的合成、理论计算及三阶非线性光学性质

合成一种非线性光学(NLO)有机材料查尔酮:1-(芘-1-基)-3-(噻吩-3-基)丙烯酮,通过1 H NMR、IR、HR-MS表征了其结构。采用4f相位相干成像技术测定了它的三阶NLO性质,相关参数为:脉宽4ns,激光波长为450nm,非线性吸收系数(β)=7.3×10-10 m/W,非线性折射率(n2)=-3.6×10-17 m2/W,三阶非线性极化率(χ(3))=4.12×10-11 esu;并测定了紫外光谱、荧光光谱和DSC曲线。采用密度泛函方法计算了它的轨道能量和极化率,结果表明电子转移可在分子内部进行,显示出良好的NLO活性。     

维生素B1催化制备2-噻吩偶姻的研究

以维生素B1为催化剂,在三乙胺为碱的条件下,催化2-噻吩甲醛发生安息香缩合反应制备噻吩偶姻,产率15％。