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111.
Peyman Salehi Mohammad M. Khodaei Mohammad A. Zolfigol Afsaneh Keyvan 《Monatshefte für Chemie / Chemical Monthly》2002,27(11):1291-1295
Crossed aldol condensations of ketones with aromatic aldehydes are carried out efficiently in the presence of magnesium hydrogensulfate under solvent-free conditions in good to excellent yield without the occurrence of any self-condensation. Similar reactions in solution do not proceed satisfactorily. 相似文献
112.
Mahmood Payehghadr Akram Zamani Ali Reza Salehi Sadaghiani Mehdi Taghdiri 《Journal of inclusion phenomena and macrocyclic chemistry》2008,62(3-4):255-261
The complexation reaction between 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane ligand (Kryptofix5) and Zn2+, Ni2+, Co2+, Pb2+ and Cu2+ ions were studied conductometrically in acetonitrile solution. The formation constants of the resulting 1:1 complexes were calculated from the computer fitting of the molar conductance and absorbance measurements in various mole ratios. The enthalpy and entropy changes of the complexation reactions were derived from titration conductometry in acetonitrile at various temperatures. At 25 °C, the stability of the resulting complexes varied in the order Pb2+ > Zn2+ > Cu2+> Co2+> Ni2+. 相似文献
113.
Emily Chizmar Colton Magnant Pouria Salehi Nowbandegani 《Graphs and Combinatorics》2016,32(3):881-886
We prove a sharp connectivity and degree sum condition for the existence of a subdivision of a multigraph in which some of the vertices are specified and the distance between each pair of vertices in the subdivision is prescribed (within one). Our proof makes use of the powerful Regularity Lemma in an easy way that highlights the extreme versatility of the lemma. 相似文献
114.
Elham Tabrizian Ali Amoozadeh Salman Rahmani Mehdi Salehi Maciej Kubicki 《Research on Chemical Intermediates》2016,42(2):531-544
A new and economical synthesis of α, α′-bis(substituted-benzylidene)cycloalkanones has been achieved by the reaction of cycloalkanones with different aromatic aldehydes using nano-TiO2/acetic acid as a catalyst in ethanol under reflux conditions with excellent yields. Five new products and three new single crystal structures are reported. 相似文献
115.
New Convenient Five‐Component One‐Pot Synthesis of 3‐Alkyl‐6‐amino‐1,4‐dihydro‐4‐{[(1,2,3‐triazol‐4‐yl)methoxy]phenyl}pyrano[2,3‐c]pyrazole‐5‐carbonitrile Derivatives 下载免费PDF全文
Minoo Dabiri Peyman Salehi Mahsa Fakharian Siyavash Kazemi Movahed David I. MaGee 《Helvetica chimica acta》2015,98(5):633-641
3‐Alkyl‐6‐amino‐1,4‐dihydro‐4‐{[(1,2,3‐triazol‐4‐yl)methoxy]phenyl}pyrano[2,3‐c]pyrazole‐5‐carbonitrile derivatives were synthesized through a one‐pot five‐component condensation reaction. 相似文献
116.
117.
Two new cobalt(III) complexes of the Schiff base N,N??-bis(methylsalicylidene)-1,2-ethylenediimine dianion (Me-Salen), trans-[Co(Me-Salen)(L)2]ClO4 (L = 3-acetylpyridine) (I) and (L = 4-acetylpyridine) (II), have been synthesized and characterized by elemental analyses, FT-IR, UV-Vis, and 1H NMR spectroscopy. The X-ray diffraction analysis reveals that I crystallizes in the monoclinic space group P21/c and displays a distorted octahedral coordination geometry about Co with the equatorial plane formed by the N2O2 donors of the tetradentate Schiff base dianion, the two phenolate O atoms and the two imine N atoms of which are each mutually in cis-position. Two 3-acetylpyridine molecules are attached to the metal atom to fill its axial positions. 相似文献
118.
Zinatossadat Hossaini Faramarz Rostami‐Charatib Rahimeh Hajinasiria Hojatollah Jafaryanc Mehdi Shahrakid 《Journal of heterocyclic chemistry》2012,49(2):402-404
A novel, convenient, and an efficient approach to the synthesis of 2H‐pyrans has been reported based on the multicomponent reaction. Solvent‐free condition for the reaction of dithiocarbamates, alkyl propiolates and isocyanides lead to the formation of 2H‐pyrans in good yields. In these reactions, synthesis of 2H‐pyrans is possible based on the one‐pot reaction and without using any catalyst. The mild reaction conditions and high yields of the products exhibit the good synthetic advantage of these methods. J. Heterocyclic Chem., lpar;2011). 相似文献
119.
A. Mousavi Moghadam M. Vafaie Sefti M. Baghban Salehi A. Dadvand Koohi M. Sheykhan 《Journal of Macromolecular Science: Physics》2013,52(10):2015-2025
In this work, a hydrogel was prepared by crosslinking of aqueous solutions of sulfonated polyacrylamide/chromium triacetate for the purpose of water shut-off treatment in oil fields. In order to screen the factors that affect the gelation time and investigate their interactions, a 32 run fractional factorial design was used in experimentation with eight factors (pH, CaCl2 concentration, crosslinker/copolymer ratio, NaCl concentration, copolymer concentration and presence or absence of sodium lactate, nanoclay, and thiouria) and one response (gelation time). Furthermore, the analysis of variance (ANOVA) was implemented as a significant tool to evaluate the quality of the quadratic model. The ANOVA results of the developed model showed it was significant with a 99% confidence limit. Among the eight factors, presence of sodium lactate, copolymer concentration, presence of nanoclay, presence of thiouria, and crosslinker/copolymer ratio had, in order, the main effects, and the interactions between sodium lactate and crosslinker/copolymer ratio and between pH and crosslinker/copolymer ratio were highly significant. 相似文献
120.
Hojatollah Khabazzadeh Esmat Tavakilinejad Kermani Daryush Afzali Asghar Amiri Arman Jalaladini 《Arabian Journal of Chemistry》2012,5(2):167-172
Polyhydroquinoline derivatives have been prepared efficiently in a one-pot synthesis via Hantzsch condensation using Cs2.5H0.5PW12O40 as a heterogeneous and reusable catalyst. The present method uses molten salt media instead of hazardous organic solvents. The present methodology offers several advantages such as simple procedure, excellent yields, and a short reaction time. 相似文献