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1.
In this work 3-chloro-2-chlorocarbonylbenzo[b]thiophene (1) was prepared from cinnamic acid and then converted into the acid hydrazide 2. The azomethines 3a-e were prepared from the corresponding aryl aldehydes and the acid hydrazide 2. Treatment of compound 2 with formic acid gave the N-formyl acid hydrazide 4, which upon refluxing with phosphorous pentoxide or phosphorous pentasulphide in xylene yielded the corresponding 2- (3-chloro-1-benzothien-2-yl)-1,3,4-oxadiazole (5) and 2-(3-chloro-1-benzo-thien-2-yl)-1,3,4- thiadiazole (6). Reaction of 1-thiosemicarbazide 7 with NaOH leads to ring closure giving 5- (3-chloro-1-benzothien-2- yl)-4H-triazole-3-thiol (8) which is converted into a number of derivatives 9-12 Reaction of 2 with phenyl isothiocyanate and NaOH afforded 5-(3-chloro- 1-benzothien-2-yl)-4-(phenyl)-4H-1,2,4-triazole-3-thiol (14). 相似文献
2.
Mohamed. R. Aouad Nadje T. Rezki El Sayed H. El Ahsry 《Journal of heterocyclic chemistry》2008,45(5):1321-1327
A solid support under microwave (MW) irradiation without solvent allowed the synthesis of the 2,3‐epoxy‐propyl‐thioimidazole 4 , regioselectively, and prohibited its cyclization to give the imidazo[2,1‐b]thiazine 3 from the reaction of 4,5‐diphenylimidazole‐2‐thione ( 1 ) with 1‐chloro‐2,3‐epoxy‐propane ( 2 ). The formation of the latter required basic conditions whereby it became the sole product; the change of the basic catalyst changed the ratio of the two products under both conventional and microwave (MW) conditions. A regioselective allylation of 1 with allyl bromide in presence of triethylamine gave the S‐allyl 8 , while in presence of potassium carbonate led to the S,N‐bis(allylated) derivative 9 . The intramolecular ring closure of 8 in presence of sulfuric acid afforded the imidazothiazole 16 . Protection of the sulfur in 1 and subsequent reaction with allyl bromide gave the N‐allylated derivative and with 2 gave N‐3‐chloro‐prop‐1‐yl derivative that shed light on the preferred route for the formation of 3 and 4 . The reactivity encountered during the alkylation of 1 with 2 has been theoretically investigated by using the AM1 method. 相似文献
3.
Aouad A. Bilali L. Benchanâa M. Mokhlisse A. 《Journal of Thermal Analysis and Calorimetry》2002,67(3):733-743
The natural phosphate and its demineralization products from Moroccan deposit were pyrolysed in a thermogravimetric analyser
(TG) to examine the influence of the heating rate and mineral matter on their thermal decomposition. The heating rates investigated
in the TG were 5–100°C min−1 to final temperature of 1200°C. The integral method was used in the analysis of the TG to determine the kinetic parameters.
It has been found that for the natural phosphate and corresponding kerogen analysed in the TG, the increase of the heating
rate shifts the maximum rate loss to higher temperature. A first order reaction was found to be adequate for pyrolysis in
the range 150–600°C which was attributed to kerogen decomposition. In addition, the results indicate that the removal of mineral
matter affected the kinetic parameters found for kerogen in the natural phosphate.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
[reaction: see text] The enantioselectivity of Rh(2)(S-DOSP)(4) catalyzed C-H insertion of aryldiazoacetates is very dependent on the site of the C-H insertion. The highest enantioselectivity is obtained for insertion into methine C-H bonds. 相似文献
5.
Samer Aouad Amal Aoun Mira Skaf Madonna Labaki John El Nakat Bilal El Khoury Pierre Obeid Edmond Abi-Aad Antoine Aboukaïs 《Comptes Rendus Chimie》2013,16(10):868-871
The effects of CoxMgyAl2Oz mixed oxides composition and ruthenium addition on the oxidation of propylene and carbon black (CB) were investigated. Different reactive cobalt and ruthenium oxide species were formed following calcination at 600 °C. The addition of ruthenium was beneficial for the CB oxidation under “loose contact” conditions and for propylene oxidation when the cobalt content was intermediate to low. The calculated activation energy for CB oxidation was decreased from 151 kJ mol−1 for the uncatalyzed reaction to 111 kJ mol−1 over the best catalyst. 相似文献
6.
7.
Aouad A. Benchanâa M. Mokhlisse A. Arafan A. 《Journal of Thermal Analysis and Calorimetry》2002,70(2):593-603
Thermogravimetry (TG), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) were used
to study the thermal behaviour of the organic matter in the natural phosphate and its concentrate kerogen from the Moroccan
deposit. The TG analysis showed that both the investigated samples exhibited a one-step thermal oxidation in the main mass
loss area, between 160 and 540°C, attributed to the hydrocarbon material. When DSC analyses of oxidation as well as pyrolysis
yielded two evolutionary stages of the hydrocarbon in this temperature range : the first one at 160-360°C and the second one
above 360°C. Pyrolytic kerogen decomposition was monitored by measuring changes in the principal FTIR organic bands. The results
showed, in the first stage, the progressive decrease of signals due to CH2 and CH3 vibrations as well as the carbonyl and carboxylic bands, and their subsequent disappearance at 300°C. In the second stage
above 400°C, the signal due to the aromatic components (1600 cm-1) appeared but decreased with increasing temperature up to 540°C.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
New heterocyclic derivatives of cyclopropane dicarboxylic acid comprising thiadiazole and 1,2,4-triazole moieties are reported. Reaction of 1,1-cyclopropane dicarboxylic acid (1) with thiosemicarbazide and phosphorous oxychloride resulted in 1,1-bis (2-amino-1,3,4-thiadiazol-5- yl)cyclopropane (2). Cyclopropane dicarboxylic acid thiosemicarbazide (6) was converted into 1,1-bis(3-thio-4H-1,2,4-triazol-5-yl) cyclo- propane (7) by ring closure in an alkaline medium. The thiadiazole 2 and the triazole 7 were converted into a variety of derivatives. 相似文献
9.
Rezki Nadjet Mayaba Mariem Mohammed Al-blewi Fawzia Faleh Aouad Mohamed Reda El Ashry El Sayed Helmi 《Research on Chemical Intermediates》2017,43(2):995-1011
Research on Chemical Intermediates - Base-catalyzed alkylation of 5-(4-fluorophenyl)-2,4-dihydro-1,2,4-triazole-3-thione (3) with one or two equivalents of propargyl bromide in presence of... 相似文献
10.
The relationship between the state of Ru on CeO2 and catalytic activity in the oxidation of carbon black (CB) and some volatile organic compounds (VOCs) was investigated
for Ru/CeO2 catalysts prepared by wet impregnation. It was demonstrated that the addition of ruthenium to ceria significantly improved
the reactivity of the latter. The temperature programmed reduction (TPR) experiments of Ru/CeO2 showed that the oxygen species of RuO2 was reduced at low temperatures. In addition, Electronic Paramagnetic Resonance (EPR) studies of outgassed samples at different
temperatures showed an anisotropic signal indicating that Ru(IV) was reduced to intermediate valence states like Ru(III) before
its total reduction to metallic Ru. It was concluded that Ru-O-Ce bonds in the well-dispersed Ru species are highly fragile
and its mobile oxygen is the active species in the catalytic oxidation process.
Published in Russian in Kinetika i Kataliz, 2007, Vol. 48, No. 6, pp. 893–898.
This article was submitted by the authors in English. 相似文献