1-arylidene-2-(5-(4-methoxyphenyl)thiazol- 2-yl)hydrazine (2a-h, Table-1) were synthesized according to scheme 1. Thiazole derivatives 2(a-h) were prepared by one pot two step condensation of aromatic aldehydes, thiosemicarbazide and phenacyl bromide. In first step aromatic aldehydes 1a-h (1 mmol), thiosemicarbazide(1 mmol) were reacted in ethanol at room temperature catalyzed by 10 mol % sulphamic acid. It was resulted in thiosemicarbazone of corresponding aromatic aldehyde. Further same flask was charged with phenacyl bromide (1 mmol) and acidic buffer, stirred till completion of reaction. Completion of reaction was monitored by thin layer chromatography technique. After completion of reaction mixture was treated with cold water, separated solid was filtered, dried and recrystallized. The products were obtained in moderate to good yield. The structures of compounds 2(a-h) were confirmed by spectroscopic methods such as IR,
The materials used in this research were 4-hydroxy-benzaldehyde, 4-hydroxy-3-methoxy benzaldehyde (vanillin), 2-bromoacetophenone (phenacyl bromide), and 2,4'-dibromo acetophenone (4'-bromo-phenacyl bromide). Triethylamine was used as the catalyst and sodium dodecyl sulfate/SDS (micellar) as co-surfactant. All chemical and solvent were purchased from Merck (except distilled water) and used without further purification.
then phenacyl bromide (PacBr), DMF, 30 min, room temperature. Commercially available reagents and solvents were used as received. Anhydrous solvents were distilled; THF was purified by distillation over sodium and benzophenone. Flash column chromatography was performed on silica gel (40–60 mm)
Synthesis of 2-acyl-3-aminonaphtho[2,1-b]furan To a solution of chloroacetic acid (0.005 mol) and sodium carbonate (0.00275 mol) in water (10 ml) was added slowly, To a solution of 2-hydroxy-1-naphthonitrile (1) (0.02 mol) while stirring for 30 min, a solution of 4a (0.0055 mol) in in dry acetone (100 ml), phenacyl bromide (0.02 mol) and sodium hydroxide (0.015 mol) in water (10 ml) and the anhydrous potassium carbonate (0.2 mol) were added and reaction mixture was stirred overnight at room the reaction mixture was refluxed on water bath for 8 h. temperature, acidified with dilute hydrochloric acid and The potassium salt was filtered off and washed thoroughly extracted with chloroform. The organic layer was dried with acetone. Removal of solvent from the filtrate and over sodium sulphate, the solvent was removed by subsequent tritution with ethanol gave 2-benzoyl-3- distillation under reduced pressure to obtain solid, which aminonaphtho[2,1-b]furan 14 (2a). The compounds 2b-2d was recrystallised from ethanol. Physical data of newly
under reflux conditions (Tables 2). However, the activ- ity of catalysts is determined by the acid–base proper- ties, surface area, the distribution of sites and the polarity of the surface sites [26, 27]. We studied the feasibility of the reaction by selecting some representative substrates (Table 3). To investigate the extent this catalytic process, phenacyl bromide or 4-methoxyphenacyl bromide, car- bon disulfide and primary amine were elected as sub- strates. Seeking of the reaction scope demonstrated that various primary amines can be utilized in this method (Table 3).
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Scheme 3 displays a proposed mechanism for this reaction in the presence of cross-PAA-SO 3 H@ nano-Fe 3 O 4 as the catalyst. Initially the nucleophilic attack by amines on a carbon disulfide generates intermediate (I). The next step involves nucleophilic attack of intermediate (I) on the methylene carbon of phenacyl bromide, leading to intermediate (II), and then ring closure by intramolecular attack of nitrogen at the carbonyl carbon to afford the 3-alkyl-4-phenyl-1,3- thiazole-2(3H)-thione deri- vatives. In this mechanism, the surface atoms of cross-PAA-SO 3 H@nano-Fe 3 O 4 activate the C=S and C=O groups for better reaction with nucleophiles.
Trihydric phenols like Pyrogallol (1,2,3 tri hydroxyl benzene), Phlorogluction (1,3,5 tri hydroxyl benzene) and Hydroxyquino (1,2,4 tri hydroxyl benzene) react with phenacyl bromide and methyl, chloro, methoxyl, bromo substituted phenacyl bromide. Here one mole of trihydric phenol is taken for the reaction and 3 moles of phenacyl and appropriately substituted phenacyl bromide. The total reaction was carried out in micellar solution 5-6 .
To a stirred solution of 5-bromofuran-2-sulfonyl amide (1.0 mmol) in acetone (25 ml) and potassium carbonate (2 eq). Added Substituted phenacyl bromide (1 eq). Stirred reaction mass at room temperature for 2h . Progress of reaction monitored by TLC. Evaporated reaction mass under reduced pressure and obtained gu mmy material added cold water (100 ml) to it and stirred reaction mass for 1 h. Solid precipitates out filter it and wash it with excess of water and
Br , adopts a layered structure consisting of alternating hydrophilic and hydrophobic regions. The ammonium groups and bromide anions interact through N + —H Br hydrogen bonds, forming transoid one-dimensional ladders, which are further linked by electrostatic N + Br interactions into two- dimensional sheets.
This study is applied research, which was carried out in a batch system with a height of 10 cm, width of 5 cm, and length of 30 cm with the capacity of one litre. There were 4 lamps (8 W, UV-C-254 nm) above the reactor (low pressure of mercury vapor) that are electrically connected to each other. This reactor was in the box that made of quartz. In this study, the colorimetric method of phenol-red was used in order to measure bromide by the spectrophotometer of model DR-2000 at a wavelength of 590 nm. Also, pH testing was performed by the Electron pH meter model CP-501 with the accuracy range (0.01) and according to standard method references (19). All of the chemical material were made in Merck Company (Germany) and ZnO nanoparticle were made in the United States. 0.2 N HCl was used in order to adjust the pH. The bromide stock solution was prepared by dissolving 0.148 g of potassium bromide salt in 100 mL of double-distilled water. In this study, the scanning electron microscope, the X-ray powder diffraction, and the transmission electron microscope were used to determine the characteristics of nanoparticles including the structure of morphology, particle size, parameters, and the stability of nanoparticles
The title compound, (I), is the seventh crystal structure in a series of alkyl-substituted triphenylphosphonium bromide compounds from this laboratory (Czerwinski, 1986, 2004; Ponnuswamy & Czerwinski, 1986; Czerwinski & Ponnuswamy, 1988a,b, 1989). The atom labelling is consistent with the previously reported structures.
Recently, our group reported the properties and X-ray crystal structure determination of triferrocenylboroxine (Ma et al., 2002). We report here the hydrolysis of the 1-(dibromo- boryl)ferrocene±dimethylethylamine (1/1) adduct and the X- ray crystal structure analysis of the resulting dimethylethyl- ammonium bromide, [HNEtMe 2 ]Br. The synthesis of
necessary for its vaporization from the water to be cooled. The saturated steam then leaves the evaporator (state 4) and feeds the absorber where the concentrated lithium bromide solution flows, which dilutes by absorbing the water vapor until saturation. This is a physical absorption that is an exothermic operation, hence the need for cooling to reach the desired concentration of saturation at the output of the absorber (state 5). The diluted solution at low pressure is pumped to the pressure required for regeneration (state 6). This transformation is supposed to be isentropic since we operate at low pressures. Concerning the cycle of the lithium bromide solution (5-6-7-8-8-9-10). It makes sense to take advantage of the high temperature of the concentrated solution leaving the generator to heat the diluted solution coming from the absorber. Since otherwise this heat will only be dissipated, which will unnecessarily require a larger exchange surface in the absorber and a larger size of the cooling tower and will penalize the COP of the machine. This is why an economizer have to be installed in the circuit (generator-absorber) . 2.2 Data and Modeling Hypotheses
24. Bhandari SV, Bothara KG, Raut MK, Patil AA, Sarkate AP, Mokale VJ. Design, Synthesis and Evaluation of Anti- inflammatory, Analgesic and Ulcerogenicity studies of Novel S- Substituted phenacyl-1,3,4-oxadiazole-2-thiol and Schiff bases of Diclofenac acid as Nonulcerogenic Derivatives. Bioorganic & Medicinal Chemistry, 16, 2007 Nov 19, 1822-1831.
Poly(triazine imide) ‒ a 2D layered network ‒ can be obtained as an intercalation compound with halides from the ionothermal condensation of dicyandiamide in a eutectic salt melt. The gallery height of the intercalated material can be tuned via the composition of the eutectic melt and post-synthetic modification. Herein, we report the synthesis of poly(triazine imide) with intercalated bromide ions (PTI/Br) from a lithium bromide and potassium bromide salt melt. PTI/Br has a hexagonal unit-cell
reflection of the small sample size as a reduction in myalgia from 46.3% with vecuronium bromide compared to 28.6% with rocuronium bromide may be considered clinically significant. A larger sample size may clarify this issue 4 . Demers and P Drolet observed severe myalgia in 8 patients of saline group compared to 1 and 2 patients in rocuronium bromide and d-tubocurarine group respectively at post operative 24 hours and 2 patients had severe myalgia in saline group compared to only 1 patient in both rocuronium bromide and d-tubocurarine group at post operative 48 hours 6 . R Martin and J Carrier noted myalgia in 71% patients. Myalgia was not diminished by pre treatment with any non depolarizing muscle relaxant. It differs from other study. They mentioned that no advantage was observed with pre-treatment except that it prevented fasciculations. 7
Quaternary alkylammonium salts are widely used to modify natural clay minerals into hydrophobic organo-clays which exhibit high capability to remove hydrophobic contaminants from aqueous solutions (Ogawa & Kuroda, 1997). From the systematic study of the relation between the crystal structures of chosen homologous benzyldimethylalkylammonium bromides and their cations′ ability for sorption on clay minerals (Kwolek et al., 2003; Hodorowicz et al., 2003, 2005), it became obvious that the hydrophobic interactions are responsible for an alkyl-chain bilayer formation when the long- chain (n = 8–12) ammonium cations are adsorbed on montmorillonite (Hodorowicz et al., 2005), whereas a different way of cation packing seems to dominate in the case of short-chain ammonium cations (Kwolek et al., 2003). The crystal structure analysis of benzyldimethylethylammonium bromide was performed to find out the influence of molecular geometry, and the length of the alkyl chain in particular, on the packing properties of the ammonium cations. The structure of the title compound is shown in Fig. 1. The asymmetric unit is composed of a quaternary ammonium cation and a bromide counterion (N + ···Br - = 4.439 (2) Å). The bond lengths and angles indicate the typical tetrahedral
Next, PTC and the solvents were screened. In Table 2, it seemed that the reaction did not happen without PTC. Only 10% mol PTC, such as TBAB (Tetrabutyl ammonium bromide), TEAB (Tetraethyl ammonium bromide), BTEAC (Benzyl triethyl ammonium chloride), CTMAB (Hexadecyl trimethyl ammonium bromide) compelled the reaction to give the product in high yield (Table 2, entries 1–5). After comparison of the solvents, DCM proved to be the best solvent (Table 2, entries 6–8).
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From the study conducted by Symons , we can see that bromine reacts faster than chlorine with natural DOM and HOBr is a stronger oxidant and is 20 times of HOCl. This was why the water with high concentration of bromide ions tended to have higher level of TTHMFP. When the concentration of bromide ions was 0.03mg/L, the amount of HOCl in water is much higher than that of HOBr, and the formation of THMs-Cl was dominant. However, with the increase of bromide ion concentration, almost all of the bromide ions were oxidized into HOBr, and the formation of
Salts having bromide anion did not initiate the cationic polymerization due to the termination process resulting from the bromide ion to the propagated cation. Table 1 shows that the product of the polymer depend on the structure of the onium salt used (anion = SbF6-), 4- nitrobenzyl polymeric phosphonium hexafluoro antimonate (salt 2) polymerize the vinyl monomers (p-methylstyren and N- vinylcarbazole), and did not initiate the cationic polymerization of cyclohexene oxide, this could be due to interaction between the polar nitro group and the propagated oxonium cation which can terminate the polymerization at early stage.