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tetrabutylammonium
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Reactivity studies of biomimetic catalytic epoxidation of alkenes with tetrabutylammonium periodate in the presence of various manganese porphyrins and nitrogen donors: Significant axial ligand π-bonding effects
, Article New Journal of Chemistry ; Volume 28, Issue 6 , 2004 , Pages 740-747 ; 11440546 (ISSN) ; Karimipour, G ; Bagherzadeh, M ; Sharif University of Technology
Royal Society of Chemistry
2004
Abstract
Highly selective epoxidation (> 95%) of unfunctionalized alkenes was performed by tetrabutylammonium periodate in the presence of six different phenyl substituted manganese(III) meso-tetraphenylporphyrins [Mn(Por)] and imidazole in CH2Cl2. Electron-withdrawing and bulky substituents on the phenyl groups lowered the catalytic activities of the corresponding Mn(Por). Less bulky alkenes with electron -rich double bonds showed greater reactivity in the epoxidation. Co-catalytic activities of four different classes of axial nitrogen donors are compared in the presence of various Mn(Por). In general no direct correlation was found between co-catalytic activities and the pKa values of the nitrogen...
Stereoelectronic effects: A simple yet powerful tool to manipulate anion affinity
, Article Organic and Biomolecular Chemistry ; Volume 13, Issue 7 , Dec , 2015 , Pages 2170-2176 ; 14770520 (ISSN) ; Fattahi, A ; Kass, S.R ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
Different strategies are employed in designing strong and selective anion receptors but stereoelectronic effects have been largely ignored. In this work, the stereo configuration of a non-interacting ether is found to have a large impact of more than two orders of magnitude on the binding of a rigid diol with tetrabutylammonium chloride in acetonitrile-d3. A favorable carbon-oxygen dipole and an intramolecular C-H⋯OH hydrogen bond in an equatorially substituted ether is found to be energetically more important than a stabilizing hydrogen bond in the corresponding axially oriented alcohol. IR spectroscopy is also used to probe the structures of the bound complexes and several binding motifs...
Development of a novel carboxamide-based off-on switch fluorescence sensor: Hg2+, Zn2+and Cd2+
, Article New Journal of Chemistry ; Volume 44, Issue 27 , June , 2020 , Pages 11841-11852 ; Bagherzadeh, M ; Meghdadi, S ; Rabiee, N ; Abbasi, A ; Schenk Joß, K ; Tahriri, M ; Tayebi, L ; Webster, T. J ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Here, the carboxamide ligand N-(thiazole-2-yl) picolinamide (L) was synthesized in an ionic liquid tetrabutylammonium bromide (TBAB) as the benign reaction medium. The sensitivity of L towards different metal-ions was investigated, and a comprehensive, logical optical investigation was conducted for the IIB transition metal ions, Hg2+, Cd2+ and Zn2+, based on off-on switch sensor protocols. In the absence of these metal ions, L showed weak emission only, but fluorescence intensity increased considerably upon their addition to a sensitivity range of 10-6 M. This phenomenon was enhanced significantly in the presence of Zn2+ compared to other metal ions, likely due to the coordination of...
2,6-Bis(diphenylphosphino)pyridine: A simple ligand showing high performance in palladium-catalyzed CN coupling reactions
, Article Tetrahedron Letters ; Vol. 55, issue. 30 , July , 2014 , p. 4098-4101 ; ISSN: 00404039 ; Rafiee, E ; Jamali, S ; Joshaghani, M ; Sharif University of Technology
Abstract
The use of commercially available 2,6-bis(diphenylphosphino)pyridine as a ligand in conjunction with K2CO3, DMAc and TBAB is an effective method for the palladium-catalyzed CN coupling of a variety of aryl halides with anilines, N-heterocyclic aromatic amines, and a cyclic secondary amine. The reactions proceed in good to excellent yield (up to 98%) while the loading of Pd(OAc)2 was as low as 0.025 mol %
Investigation of the interfacial electron transfer kinetics in ferrocene-terminated oligophenyleneimine self-assembled monolayers
, Article Langmuir ; Volume 36, Issue 42 , 2020 , Pages 12572-12579 ; Sharif University of Technology
American Chemical Society
2020
Abstract
In this article, the synthesis, characterization, and cyclic voltammetry (CV) measurements are reported for ferrocene-terminated oligophenyleneimine (OPI_Fc) and ferrocene-terminated conjugation-broken oligophenyleneimine (CB-OPI_Fc) self-assembled monolayers (SAMs) in two different electrolytes, namely, 1-ethyl-3-methylimidazolium-bis (trifluoromethyl-sulfonyl) imide (EMITFSI) ionic liquid and tetrabutylammonium hexafluorophosphate (Bu4NPF6) in acetonitrile (0.1 M solution). The SAMs were synthesized on Au surfaces by the sequential imine condensation reactions. CV was used to investigate the kinetics of electron transfer (ET) to the ferrocene, and it was observed that the standard ET rate...