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substitution that requires Lewis acids or strong mineral acids. Selective alkylation of aromatic hydrocarbons has been extensively studied over various zeolites and summarized in many reports [ 1 – 4 ]. A mechanistic overview on the acylation of anisole using α

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Abstract  

In the present study, non-conventional solid acid catalysts such as NaY, metal ion exchanged zeolite NaY (Zn2+, Fe3+, Ce3+, La3+ and Nd3+), H-mordenite, H-β and HZSM-5 were used in order to overcome the disadvantages of conventional Friedel-Crafts catalysts for the acylation of anisole with acetic anhydride. Among the various zeolites studied, the HY zeolite shows an intermediate activity. Zeolite containing transition metal ions (Zn2+ and Fe3+) are less active and zeolite NaY is nearly inactive. The catalysts exhibit the activity in the order H-β>transition metal ions (Zn2+ and Fe3+)>HY>NaY zeolite. The highest catalytic activity of H-β could be due to its larger pore size. The type of acidity and the acid strength in zeolite Y were determined by FTIR and differential scanning calorimetric (DSC) studies on the pyridine adsorbed catalysts. The correlation of catalytic activity with acidity reveals that Brönsted acid sites in zeolite promote the acylation of anisole.

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Abstract  

Poly(2-hydroxymethyl methacrylate) (PHEMA) suspension in anisole shows temperature dependent iridescence between 0 and 60C. To reveal the mechanism of the temperature-dependent iridescence, PHEMA-anisole mixtures were prepared, and their thermal behaviors have been studied by dynamic DSC (DDSC) technique. All the mixtures showed a broad peak at 325 K on loss part of DDSC curves (loss C pcurve), and showed a gentle step change between 250 and 340 K on the storage part (storageC p curve). A temperature region of these changes matched the observation of iridescence change. Temperature of the step change depended on the composition of mixture. The temperature dependence of iridescence of the polymer mixture has been attributed to the conformational changes of PHEMA chains.

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psi (CO/H 2 = 1/2), 2 h, temperature (°C) a Determined by GC using anisole as internal standard

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-propanol containing NaOH. The main product was anisole, but 4,4′-dimethoxybiphenyl (4,4′-DMB) could also be produced (Chart 1 , Eq. 1) [ 11 ]. Table 1 summarizes the conversion of p -chloroanisole and the yield of chlorine-free products after a 10-min

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Journal of Thermal Analysis and Calorimetry
Authors: Corina Duda-Seiman, T. Vlase, Gabriela Vlase, Rodica Cinca, Mariana Anghel, and N. Doca

corresponding DTG max and DTA max was observed. In order to elucidate these thermally induced phenomena, the IR data is useful. The spectrum of the evolved gases, drawn up at 288 °C (first DTG max ) indicates water, carbon dioxide, and anisole

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methanol and anisole, the latter (phenyl alkyl ether) has characteristic peaks at 1250 and 1040 cm −1 related to the axial asymmetric and symmetric deformation C–O–C, respectively, and two peaks at 1594 and 1491 cm −1 , related to C=C of the ring

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(calculated mass loss 54%). Fig. 3 EG spectrum at 360 °C. Water vapors and carbon dioxide are the main compounds detected (also small anisole-like derivatives

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respect to iodobenzene and methyl acrylate concentration. A first order dependence with respect to 4-iodo-anisole and Pd has been reported by Nilsson and Wendt [ 25 ] for the kinetics of the coupling of 4-iodo-anisole and styrene over a PdI 2 /PCP pincer

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antioxidants, for instance butyl-hydroxide-anisole (BHA), butyl-hydroxide-toluol (BHT), ethoxy-methyl-quinoline (EMQ) and propyl-gallate (PG). Another process which occurs during the perishing of fats is hydrolysis. During storage, the quantity of free fatty

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