138564-58-6Relevant articles and documents
Easy single-step preparation of ZnO nano-particles by sedimentation method and studying their catalytic performance in the synthesis of 2-aminothiophenes via Gewald reaction
Tayebee, Reza,Javadi, Farzad,Argi, Gholamreza
, p. 16 - 23 (2013)
Zinc oxide is a multi-purpose active material with important catalytic applications. In this study, nano-sized ZnO particles were easily synthesized through sedimentation of zinc acetate di-hydrate in absolute ethanol and were characterized by XRD and SEM. The XRD results indicated pure wurtzite structure with the average particle size of 26.9 nm for the nano-particles. It was observed that size of ZnO nano-particles was decreased while solution concentration was increased. This observation would be explained considering enhancing nucleation processes of nano-particles at high concentration of zinc acetate. The prepared nano-particles (2.5 mol%) were used as catalyst for the fast and efficient synthesis of 2-aminothiophenes under solvent free conditions. The three-component mixture of a carbonyl compound, malonodinitrile, and elemental sulfur was converted into the corresponding 2-aminothiophene in moderate to high yields with excellent selectivity.
Conformational Color Polymorphism and Control of crystallization of 5-Methyl-2-[(4-methyl-2-nitrophenyl)amino]-3-thiophenecarbonitrile
He, Xiaorong,Griesser, Ulrich J.,Stowell, Joseph G.,Borchardt, Thomas B.,Byrn, Stephen R.
, p. 371 - 388 (2001)
5-Methyl-2-[(4-methyl-2-nitrophenyl)amino]-3-thiophenecarbonitrile is an example of conformational and color polymorphism. The compound crystallizes in red (R), dark red (DR), light red (LR), and orange (O) modifications. There are two specific goals for this study. One is to characterize the complex thermodynamic relationship among these four known forms, and the other is to use the knowledge of the thermodynamic relationship to control the crystallization of these forms. The different forms were characterized by X-ray powder diffractometry as well as Fourier-transform infrared (FT-IR) and Raman spectroscopy; their complex thermodynamic relationships were determined by thermal analysis, solubility measurements, and slurry conversion studies. According to the solubility results, all forms are enantiotropically related: R is the thermodynamically most stable form above 60 deg C, O is the most stable form between room temperature and 60 deg C, LR is the most stable form below - 15 deg C, and DR is metastable throughout the entire temperature range. DR, LR, and O have very similar free energy at ambient temperature, which is the reason for the complex transition behavior. Finally, a schematic energy - temperature diagram was constructed that combines all experimental data in a comprehensive thermodynamic picture and provides insights into how to control the crystallization of the individual forms.
Facile pathway for synthesis of two efficient catalysts for preparation of 2-aminothiophenes and tetrahydrobenzo[b]pyrans
Saadati-Moshtaghin, Hamid Reza,Zonoz, Farrokhzad Mohammadi
, p. 2195 - 2213 (2017/12/18)
Abstract: We report here a new magnetically recyclable catalyst consisting of iron-substituted Keggin-type heteropolyacid (HPA) grafted on modified Fe3O4 nanoparticles. The synthesized hybrid nanomaterial exhibited the excellent catalytic efficiency in condensation reaction for the preparation of tetrahydrobenzo[b]pyrans under solvent-free conditions as well as in the synthesis of 2-aminothiophenes via Gewald reaction. It must be noted that, HPA supported magnetite nanoparticles catalyzed the preparation of tetrahydrobenzo[b]pyrans, whereas for Gewald reaction amine-functionalized magnetite nanoparticles acted as a catalyst. Different characterization techniques such as Fourier transform infrared (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) were used to characterize the hybrid nanomaterial. The reusability of catalyst was affirmed by using in consecutive runs for five times. Performance of prepared catalyst was compared with the various previously reported catalysts; the newly synthesized catalysts found to be most efficient with regard to reaction time, yield and ease of catalyst separation. Graphical Abstract: [Figure not available: see fulltext.].
[11C]Olanzapine, radiosynthesis and lipophilicity of a new potential PET 5-HT2 and D2 receptor radioligand
Gao, Mingzhang,Shi, Zenas,Wang, Min,Zheng, Qi-Huang
, p. 1953 - 1956 (2013/04/23)
Olanzapine and its precursor desmethyl-Olanzapine were synthesized from malononitrile, propionaldehyde, 1-fluoro-2-nitrobenzene, and substituted piperazine in 4, 4, 5, and 5 steps with 35%, 32%, 26%, and 32% overall chemical yield, respectively. [11C]Olanzapine was prepared from desmethyl-Olanzapine with [11C]CH3OTf through N-[ 11C]methylation and isolated by HPLC combined with solid-phase extraction (SPE) in 40-50% radiochemical yield based on [11C]CO 2 and decay corrected to end of bombardment (EOB), with 370-740 GBq/μmol specific activity at EOB. The calculated Log P (C Log P) value of [11C]Olanzapine is 3.39.
