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131.
Samira Jabbour 《代数通讯》2013,41(19):2221-2236
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[Fe(III)(salophen)]Cl in molten tetrabutylammonium bromide was used as a cost effective and efficient catalytic system for the electrophilic reaction of indole with carbonyl compounds. The remarkable features of this new procedure are high conversions, short reaction time, clean reaction profiles and simple experimental and work‐up procedures. 相似文献
135.
Hojatollah Khabazzadeh Iran Sheikhshoaie Samira Saeid-Nia 《Transition Metal Chemistry》2010,35(1):125-127
An efficient synthesis of various substituted Hantzsch-1,4-dihydropyridines and hexahydroquinolines, using a molybdenum(VI) complex as homogenous catalyst, from aldehydes, β-keto esters or cyclohexadiones and ammonium acetate in molten tetrabutyl ammonium bromide as an ionic liquid is described. This novel method consistently gave excellent yields (70–92%) and short reaction times (7–30 min). 相似文献
136.
Seidel R Ghadimi S Lange KM Bonhommeau S Soldatov MA Golnak R Kothe A Könnecke R Soldatov A Thürmer S Winter B Aziz EF 《Journal of the American Chemical Society》2012,134(3):1600-1605
The nonradiative dark channels in the L-edge fluorescence spectra from transition-metal aqueous solution identify the ultrafast charge-transfer processes playing an important role in many biological and chemical systems. Yet, the exact origin of such spectral dips with respect to the X-ray transmission spectrum has remained unclear. In the present study we explore the nature of the underlying decay mechanism of 2p core-excited Co(2+) in water by probing the nonradiative Auger-type electron emission channel using photoelectron spectroscopy from a liquid microjet. Our measurements demonstrate unequivocally that metal-to-water charge transfer quenches fluorescence and will inevitably lead to a dip in the total-fluorescence-yield X-ray absorption spectrum. This is directly revealed from the resonant enhancement of valence signal intensity arising from the interference of two identical final states created by a direct and Auger-electron emission, respectively. 相似文献
137.
Ttrans‐3,5‐dihydroperoxy‐3,5‐dimethyl‐1,2‐dioxalane has been used as new, effective, solid, inexpensive and nontoxic oxidant for in situ generation of Br+ from HBr. This system has been applied as catalyst for synthesis of 2‐aryl‐1H‐benzothiazoles and 2‐aryl‐1‐arylmethyl‐1H‐benzimidazoles at room temperature in excellent yields and high purity. 相似文献
138.
The first application of in situ-generated N-thiocyanatosuccinimide (NTS) for the thiocyanation of alcohols is described. This method can be easily applied for the facile conversion of primary, secondary and tertiary alcohols into the corresponding alkyl thiocyanates or alkyl isothiocyanates in good to excellent yields. 相似文献
139.
A multi-component synthesis of 3-aryl-1-(arylmethylideneamino)pyrrolidine-2,5-diones is described. A mixture of N-isocyaniminotriphenylphosphorane, an aldehyde, and Meldrum's acid undergo a 1:2:1 addition reaction under mild conditions to afford the title compounds in good to excellent yields. 相似文献
140.
Mitra Ghassemzadeh Samira Bahemmat Masoomeh Mahmoodabadi Babak Rezaii-Rad Hassan Hosseini Monfared Effat Mottefakeri Bernhard Neumüller 《Polyhedron》2010
The reaction of AMTT (AMTT = 4-amino-3-methyl-1,2,4-triazol-5-thione, HL1) with palladium(II) chloride and triphenylphosphane as a co-ligand in acetonitrile afforded the mononuclear PdII-complex [(PPh3)Pd(HL1)Cl]Cl·2CH3CN (1). The complex [(PPh3)Pd(HL1)I]Cl·1/2H2O (2) was prepared via halogen exchange between 1 and sodium iodide in methanol/acetonitrile. The first binuclear palladium(II) complex containing singly deprotonated HL1, [(PPh3)2ClPd(L1)Pd(PPh3)Cl]Cl·1/3H2O·CH3OH (3), was prepared by the reaction of HL1 with palladium(II) chloride and triphenylphosphane in the presence of sodium acetate in methanol. 相似文献