- Synthesis, nucleation, growth, structural, spectral, thermal, linear and nonlinear optical studies of novel organic NLO crystal: 4-fluoro 4-nitrostilbene (FONS)
-
A novel organic nonlinear optical material 4-fluoro 4-nitrostilbene (FONS), with molecular formula (C14H10FNO2) has been synthesized. Using ethyl methyl ketone as solvent, the synthesized material has been repeatedly recrystallized to minimize the impurities and good optical quality single crystals were harvested by slow evaporation method. Single crystal X-ray diffraction analysis reveals that the grown FONS crystal belongs to monoclinic system with noncentrosymmetric space group P2 1 . The powder X-ray diffraction pattern of FONS has been recorded. Functional groups of the title compound were confirmed by FTIR and the molecular structure was confirmed by 1H NMR. The UV-vis-NIR absorption study reveals no absorption in the visible region and the cut-off wavelength was found to be at 408 nm. Optical band gap (Eg) of the grown crystal was found to be 3.27 eV and also the optical constants were determined. Thermal behaviour of the FONS has been studied by TGA/DTA analyses. From the mass spectrum, the ratio of compound formation of FONS was analyzed. The NLO property has been confirmed by Kurtz and Perry powder SHG technique and the SHG efficiency of FONS (262 mV) crystal was found to be 12 times greater than that of KDP (21.7 mV).
- Dinakaran, Paul M.,Kalainathan
-
-
Read Online
- Discovery of styrylaniline derivatives as novel alpha-synuclein aggregates ligands
-
Parkinson's disease (PD) is the second most common neurodegenerative disorder. Early diagnosis is the key to treatment but is still a great challenge in the clinic now. The discovery of alpha-synuclein (α-syn) aggregates ligands has become an attractive s
- Bian, Jiang,Liu, Yi-Qi,He, Jie,Lin, Xin,Qiu, Chen-Yang,Yu, Wen-Bo,Shen, Yan,Zhu, Ze-Yun,Ye, De-Yong,Wang, Jian,Chu, Yong
-
-
- Immobilized Pd on Eggshell Membrane: A powerful and recyclable catalyst for Suzuki and Heck cross-coupling reactions in water
-
A stable heterogeneous palladium catalysts, the waste eggshell membrane (ESM) anchored Pd complex, was synthesized by a simple and green technique. The catalyst obtained can display an outstanding catalytic activity for Suzuki and Heck coupling reactions in water media. The reactions of various aryl halides with aryl boronic acids and terminal alkenes provided the corresponding products in moderate to excellent yields. More importantly, this novel and efficient catalyst with high stability can be easily reused for at least twelve times with no decrease of the catalytic activity, performing an endurable and wide tolerance of the substrates. Facile synthesis, high catalytic activity, and recyclability make these catalysts interesting for further studies.
- Wu, Shang,Jiang, Hongyan,Zhang, Hong,Zhao, Lianbiao,Yuan, Peilin,Zhang, Ying,Su, Qiong,Wang, Yanbin,Wu, Lan,Yang, Quanlu
-
-
- Multibond Forming Tandem Reactions of Anilines via Stable Aryl Diazonium Salts: One-Pot Synthesis of 3,4-Dihydroquinolin-2-ones
-
A fast and effective one-pot tandem process that generates Heck coupled products from readily available anilines via stable aryl diazonium tosylate salts was developed. The mild and simple procedure involves rapid formation of aryl diazonium salts using a polymer-supported nitrite reagent and p-tosic acid, followed by a base-free Heck-Matsuda coupling with acrylates and styrenes. Using 2-nitroanilines as substrates, the one-pot tandem process was extended for the direct synthesis of 3,4-dihydroquinolin-2-ones. In this case, following diazotization and Heck-Matsuda coupling to give methyl cinnamates, addition of hydrogen and reutilization of the palladium catalyst for reduction of the nitro group and hydrogenation of the alkene resulted in efficient formation of 3,4-dihydroquinolin-2-ones. The synthetic utility of this one-pot, four-stage process was demonstrated with the five-pot synthesis of a quinolinone-based sodium ion channel modulator.
- Faggyas, Réka J.,Grace, Megan,Williams, Lewis,Sutherland, Andrew
-
p. 12595 - 12608
(2018/10/15)
-
- Heck, Sonogashira, and Hiyama reactions catalyzed by palladium nanoparticles stabilized by tris-imidazolium salt
-
Palladium nanoparticles, prepared by the hydrogenation of Pd(dba) 2 in the presence of a tris-imidazolium iodide as stabilizer, act as an efficient catalyst for Heck and copper-free Sonogashira reactions with a range of aryl iodides and bromides at 0.2 mol-% Pd loading. Moreover, we describe a convenient protocol for the fluoride-free Hiyama coupling of vinylsilanes with aryl iodides that involves the use of sodium hydroxide as promoter in a methanol/water mixture. Under the developed conditions, one-pot, double Heck and Hiyama-Heck reactions are successfully achieved.
- Planellas, Marc,Moglie, Yanina,Alonso, Francisco,Yus, Miguel,Pleixats, Roser,Shafir, Alexandr
-
supporting information
p. 3001 - 3008
(2014/05/20)
-
- N-heterocyclic carbene-palladium(II)-1-methylimidazole complex catalyzed Mizoroki-Heck reaction of aryl chlorides with styrenes
-
A well-defined N-heterocyclic carbene-palladium(II)-1-methylimidazole [NHC-Pd(II)-Im] complex 1 was found to be an effective catalyst for the Mizoroki-Heck reaction of a variety of aryl chlorides with styrenes. Both activated and deactivated aryl chlorides work well to give the corresponding coupling products in good to excellent yields by using tetrabutylammonium bromide (TBAB) as the ionic liquid.
- Gao, Ting-Ting,Jin, Ai-Ping,Shao, Li-Xiong
-
supporting information
p. 1916 - 1919
(2013/01/16)
-
- Microwave-assisted solvent-free synthesis of (E)-stilbenes
-
An efficient synthesis of a series of stilbenes is reported using 4-nitrotoluene and substituted arylaldehydes as starting materials in the presence of Cs2CO3 and polyethylene glycol under solvent-free microwave irradiation. Compared with conventional method, this strategy exhibited higher stereoselectivity, shorter reaction times and has a lower environmental impact.
- Wang, Liu-Chang,Li, Jiang,Zhang, Xi-Quan,Gu, Hong-Mei,Li, Bao-Lin
-
experimental part
p. 231 - 234
(2012/09/08)
-
- Bimetallic catalysis involving dipalladium(I) and diruthenium(I) complexes
-
Dipalladium(I) and diruthenium(I) compounds bridged by two [{(5,7-dimethyl-1,8-naphthyridin-2-yl)amino}carbonyl]ferrocene (L) ligands have been synthesized. The X-ray structures of [Pd2L2][BF 4]2 (1) and [Ru2L2(CO) 4][BF4]2 (2) reveal dinuclear structures with short metal-metal distances. In both of these structures, naphthyridine bridges the dimetal unit, and the site trans to the metal-metal bond is occupied by weakly coordinating oxygen from the amido fragment. The catalytic utilities of these bimetallic compounds are evaluated. Compound 1 is an excellent catalyst for phosphine-free, Suzuki cross-coupling reactions of aryl bromides with arylboronic acids and provides high yields in short reaction times. Compound 1 is also found to be catalytically active for aryl chlorides, although the corresponding yields are lower. A bimetallic mechanism is proposed, which involves the oxidative addition of aryl bromide across the Pdi£ Pd bond and the bimetallic reductive elimination of the product. Compound 1 is also an efficient catalyst for the Heck cross-coupling of aryl bromides with styrenes. The mechanism for aldehyde olefination with ethyl diazoacetate (EDA) and PPh3, catalyzed by 2, has been fully elucidated. It is demonstrated that 2 catalyzes the formation of phosphorane utilizing EDA and PPh3, which subsequently reacts with aldehyde to produce a new olefin and phosphine oxide. The efficacy of bimetallic complexes in catalytic organic transformations is illustrated in this work. Good couple: Metal-metal singly bonded [PdIi£PdI] and [RuIi£RuI] complexes exhibit bimetallic synergy in the catalytic Ci£C bond-coupling and aldehyde-olefination reactions, respectively (see figure). Copyright
- Das, Raj K.,Saha, Biswajit,Rahaman, S. M. Wahidur,Bera, Jitendra K.
-
scheme or table
p. 14459 - 14468
(2011/03/19)
-
- N-acylamino benzyl ether derivatives
-
This invention relates to N-acylamino aryl derivatives of the formula 1where R1, R21, R22, R23, R3, R4, R5 R6, R7, R8, R, and n are as defined herein and where X is —CHRO, —OCHR—, —CH2S—, —SCH2—, —CH2CH2—, —CH=CH— or —C≡C—. The compounds of the invention are selective monoamine oxidase B inhibitors, and they are therefore useful in the treatment of diseases mediated by monoamine oxidase B, for example, for the treatment of Alzheimer's disease or senile dementia.
- -
-
-
- N-ACYLAMINOBENZENE DERVATIVES AS SELECTIVE MONOAMINE OXIDASE B INHIBITORS
-
This invention relates to N-acylamino aryl derivatives of the general formula (I), wherein R1 is halogen, halogen-(C1-C6)-alkyl, cyano, C1-C6-alkoxy or halogen-(C1-C6)-alkoxy; R
- -
-
-