Authors:P. V. Surse, S. Wagholikar, S. Mayadevi, and S. Sivasanker
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
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
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 Cpcurve), and showed a gentle step change between 250 and 340 K on the storage part (storageCp 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.
-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
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
Authors:C. T. Carvalho, F. J. Caires, L. S. Lima, and M. Ionashiro
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
Authors:Sangeeta Vijay Jagtap and Raj Madhukar Deshpande
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
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