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Showing papers on "Ether published in 1998"


Journal ArticleDOI
TL;DR: A new monomer, sodium 5,5'-carbonylbis(2-fluorobenzenesulfonate) was synthesized by sulfonation of 4,4'-difluorobenzophenone with fuming sulfuric acid as discussed by the authors.
Abstract: A new monomer, sodium 5,5'-carbonylbis(2-fluorobenzenesulfonate) (1), was synthesized by sulfonation of 4,4'-difluorobenzophenone (2) with fuming sulfuric acid Poly(ether ether ketone)s containing sodium sulfonate groups were synthesized directly via aromatic nucleophilic substitution from the sodium sulfonate-functionalized monomer 1 and Bisphenol A (3) in the presence of potassium carbonate in dimethyl sulfoxide The polycondensation proceeds without any side reactions The differential scanning calorimetry measurement indicated that the polymers are amorphous and the glass transition temperatures increase with the content of sodium sulfonate groups in the polymer chain The degree of substitution with sodium sulfonate groups has strong influence on their thermal stability and solubility

186 citations


Journal ArticleDOI
TL;DR: In this article, the hypervalent iodine(III)-induced intramolecular biaryl coupling reaction of phenol ether derivatives (nonphenolic derivatives) was investigated with the aim of preparing various dibenzo heterocyclic compounds.
Abstract: The hypervalent iodine(III)-induced intramolecular biaryl coupling reaction of phenol ether derivatives (nonphenolic derivatives) was investigated with the aim of preparing various dibenzo heterocyclic compounds. 1,3-Diarylpropanes (1a−e), N-benzyl-N-phenethylamines (2a−c) and N,N-dibenzylamines (3a−e) react with a hypervalent iodine reagent, phenyliodine(III) bis(trifluoroacetate) (PIFA), containing BF3·Et2O in CH2Cl2 to give the biaryl coupling products (4−6) in good yield. As an application of the reaction, we examined the synthesis of oxygen- and sulfur-containing dibenzoheterocyclic compounds (12−15), whose side chain moiety could be easily cleaved by the known method to give 2,2‘-substituted biphenyl compounds (16−18).

173 citations


Journal ArticleDOI
TL;DR: In this article, a metal insertion into the strong sp2−sp3 aryl−O bond was shown to occur directly, with no intermediacy of C−H activation or insertion into adjacent weaker ArO−CH3 bond.
Abstract: Reaction of [RhCl(C8H14)2]2 (C8H14 = cyclooctene) with 2 equiv of the aryl methyl ether phosphine 1 in C6D6 results in an unprecedented metal insertion into the strong sp2−sp3 aryl−O bond. This remarkable reaction proceeds even at room temperature and occurs directly, with no intermediacy of C−H activation or insertion into the adjacent weaker ArO−CH3 bond. Two new phenoxy complexes (8 and 9), which are analogous to the product of insertion into the ArO−CH3 bond (had it taken place) were prepared and shown not to be intermediates in the Ar−OCH3 bond cleavage process. Thus, aryl−O bond activation by the nucleophilic Rh(I) is kinetically preferred over activation of the alkyl−O bond. The phenoxy Rh(I)−η1-N2 complex (8) is in equilibrium with the crystallographically characterized Rh(I)−μ-N2−Rh(I) dimer (12). Reaction of [RhCl(C8H14)2]2 with 2 equiv of the aryl methyl ether phosphine 2, PPh3, and excess HSiR3 (R = OCH2CH3, CH2CH3) results also in selective metal insertion into the aryl−O bond and formation o...

161 citations


Journal ArticleDOI
TL;DR: In this paper, the structure of 2-hydroxy Schiff bases has been characterized by elemental analysis, IR, 1H-NMR and UV-visible techniques and the structure has been examined crystallographically.

157 citations


Journal ArticleDOI
TL;DR: In this article, the effect of micelles on the Diels−Alder reaction with cyclopentadiene (2) has been investigated, and it was shown that in the absence of catalytically active transition-metal ions, micells invariably retard the reaction.
Abstract: The effect of micelles of sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), dodecyl heptaoxyethylene ether (C12E7), and copper and zinc didodecyl sulfate (M(DS)2) on the Diels−Alder reaction of 3-(para-substituted phenyl)-1-(2-pyridyl)-2-propen-1-ones 1a−g, containing neutral, cationic, or anionic substituents, with cyclopentadiene (2) has been studied. In the absence of catalytically active transition-metal ions, micelles invariably retard the reaction. This can be rationalized on the basis of different binding locations of the reaction partners in the micelle. These binding sites have been probed using solubilizate-induced aromatic shifts in the 1H NMR spectrum of the surfactant and paramagnetic counterion-induced relaxation enhancements of the 1H NMR signals of the solubilizate. In contrast to SDS, CTAB, and C12E7, Cu(DS)2 micelles catalyze the Diels−Alder reaction between 1 and 2 with extremely high efficiency, leading to rate enhancements up to 1.8 × 106 compared to the uncatalyzed...

152 citations


Journal ArticleDOI
TL;DR: In this paper, small block copolymers consisting of a hydrophilic poly(ethylene glycol) block and a second, also hydrophilic, moiety which strongly interacts with alkaline earth ions were synthesized by diverse reaction sequences based on poly(methylene glycoacetyl ethers (MW = 2000 and 5000 g/mol, respectively).
Abstract: Small block copolymers consisting of a hydrophilic poly(ethylene glycol) block and a second, also hydrophilic, moiety which strongly interacts with alkaline earth ions were synthesized by diverse reaction sequences based on poly(ethylene glycol) monomethyl ethers (MW = 2000 and 5000 g/mol, respectively). These starting blocks were transferred to the poly(ethylene glycol) monomethyl monoglycidyl ether or to poly(ethylene glycols) with one terminal acid chloride group. Both intermediates were subsequently reacted with poly(ethyleneimine) (MW = 700 g/mol) and bromoacetic acid to yield poly(ethylene glycol)-block-poly[(N-carboxymethyl)ethyleneimine] (PEG-b-PEIPA, average MW = 3800 resp. 6800 g/mol) as a polymeric analog of EDTA. The terminal epoxy group is also convenient for the connection of simple peptide sequences. For the desired purpose of ion binding, poly(aspartic acid) (PAsp) was applied, resulting in the block copolymer PEO-b-PAsp. A simple testing procedure concerning the inhibition of calcium carbonate precipitation was applied for the prepared structures. A comparison with commercial builders for water treatment such as poly[(acrylic acid)-co-(maleic anhydride)] or poly(aspartic acid) stresses the superb calcium carbonate crystallization inhibition efficiency (up to the 20 fold) of the double hydrophilic block copolymer stabilizers.

142 citations


Journal ArticleDOI
TL;DR: The chelating ligand bis[2-(diphenylphosphino)phenyl] ether (DPEphos), in combination with palladium acetate, forms a highly active catalyst system for the coupling of anilines with aryl bromides.

125 citations


Journal ArticleDOI
TL;DR: The relative concentration of these aromatic alcohols and ethers in the barrel-aged wines was consistent with the observed stability of the furan derivatives, but low concentrations of vanillyl alcohol andVanillyl ethyl ether observed in all samples showed that factors other than solvolytic degradation were responsible for reducing the concentration ofThese compounds in wine.
Abstract: Furfural, 5-methylfurfural, and vanillin co-occurred in 64 barrel-aged red, white, and model wines with the reduction products, furfuryl alcohol, 5-methylfurfuryl alcohol, and vanillyl alcohol, and with the corresponding ethyl ethers of these alcohols. Hydrolytic studies in a model wine have shown that 5-methylfurfuryl ethyl ether is formed rapidly from 5-methylfurfuryl alcohol, but both decomposed quickly under the conditions. Vanillyl ethyl ether was also formed relatively rapidly, and both this ether and vanillyl alcohol were stable in the model wine. The formation of furfuryl ethyl ether from furfuryl alcohol and the subsequent decomposition of these two compounds were comparatively slow. The relative concentration of these aromatic alcohols and ethers in the barrel-aged wines was consistent with the observed stability of the furan derivatives, but low concentrations of vanillyl alcohol and vanillyl ethyl ether observed in all samples showed that factors other than solvolytic degradation were responsible for reducing the concentration of these compounds in wine. Furfuryl ethyl ether, which had an aroma threshold of 430 µg/L in a white wine, was found at approximate concentrations of up to 230 µg/L in the wines.

114 citations


Journal ArticleDOI
TL;DR: The Wells-Dawson acid was used as a catalyst for producing methyl tert-butyl ether (MTBE) from methanol and isobutylene in the gas phase at 373 K.
Abstract: The Wells–Dawson acid was studied as a catalyst for producing methyl tert-butyl ether (MTBE) from methanol and isobutylene in the gas phase at 373 K. Thus, pure Wells–Dawson acid was synthesized and characterized by 31 P NMR, XRD, FTIR and TGA-DTA measurements. The results indicated that the Dawson acid keeps its heteropolyoxoanion structure up to 873 K. The samples were active and very selective (close to 100%) for MTBE production and showed stable behavior during the reaction period of 3 h. The conversion observed on reference catalyst Amberlyst 15-wet under the same conditions was significantly lower. The acid was also tested in methanol dehydration to dimethyl ether at 373 K. For both reactions, the catalytic activity depends on the pretreatment temperature of the acid. The activity was approximately constant up to 473 K; then activity decreased steadily until becoming null when pretreatment temperature was 673 K. The catalytic results were explained using the pseudoliquid phase behavior concept.

112 citations


Journal ArticleDOI
TL;DR: In this article, a series of low molecular weight dimeric 1,3,5-triazine ethers with high glass transition temperatures is synthesized from 2-(4-fluorophenyl)-4,6-diphenyl-1, 3, 5, 5 triazine and various bisphenols and the properties of these materials are examined using differential scanning calorimetry and cyclic voltammetry, respectively.
Abstract: A series of low molecular weight dimeric 1,3,5-triazine ethers with high glass transition temperatures is synthesized from 2-(4-fluorophenyl)-4,6-diphenyl-1,3,5-triazine and various bisphenols. The thermal and electrochemical properties of these materials are examined using differential scanning calorimetry and cyclic voltammetry, respectively. The glass transition temperatures (Tg) are in the range of 106−144 °C, and all of them have similar thermal stability and show no weight loss up to 380 °C in thermogravimetric measurements. Some of these dimers form stable glasses which do not recrystallize on annealing at or above the Tg. Cyclic voltammetry studies reveal that these compounds undergo reversible reduction between −2.09 and −2.27 V vs ferrocene/ferrocenium as internal standard which correspond to LUMO values between −2.5 and −2.7 eV, respectively. The application of one of these dimeric ethers as a hole-blocking/electron-transport material in organic light-emitting devices is demonstrated.

105 citations


Journal ArticleDOI
TL;DR: The reaction of 1 equiv of (Et2O)LiC6H3-2,6-Trip2 (Trip = C6H2-2-4,6i-Pr3) with either GeCl2−dioxane or SnI2 in ether affords the synthetically useful monomeric aryl−metal halides Ge(Cl){C 6H 3-2.6-6-...

Patent
06 Apr 1998
TL;DR: In this paper, a method for dry-cleaning garments which comprises treating the garments with a mixture of propylene glycol tertiary-butyl ether (PG-THB) or PG-N-Butyl ether and water was proposed.
Abstract: A method for dry-cleaning garments which comprises treating the garments with a mixture of propylene glycol tertiary-butyl ether or propylene glycol n-butyl ether and water.

Patent
24 Jul 1998
TL;DR: In this article, a free radical photoinitiator was used for free radical, radiation curable coating of polyester polyester with unsaturated backbone and at least one compound having one to six propenyl ether groups.
Abstract: Composition suitable for free radical, radiation curable coating comprising at least one polyester having unsaturated backbone and at least one compound having one to six propenyl ether groups, and optionally, a free radical photoinitiator. The equivalent ratio of propenyl ether groups to maleimide, maleate and/or fumarate groups in the polyester is preferably about 5:1 to 1:5. The process for curing the composition includes exposing it to ionizing radiation and/or ultraviolet light. The resultant cured coatings and coated articles are similar in performance to their vinyl ether analogues, but the propenyl ethers are easier to prepare than the vinyl ether analogues.

Patent
16 Jan 1998
TL;DR: In this paper, a polymer compound is obtained by polymerizing a compound expressed by a formula between opposite electrodes of which at least one electrode is crystal or semi-crystal, and electron ray irradiation is applied to this thin film layer.
Abstract: PROBLEM TO BE SOLVED: To provide an organic electroluminescent element requiring few manufacturing processes capable of easily achieving a large area and improved in electroluminescent luminance by using a polymer compound soluble in various solvents and capable of easily forming a thin film with no pin hole. SOLUTION: This electroluminescence element is provided with a thin film containing a polymer compound obtained by polymerizing a compound expressed by a formula between opposite electrodes of which at least one electrode is crystal or semi-crystal. In addition, electron ray irradiation is applied to this thin film layer. In the formula, L denotes a dihybrid link group, R denote a hydrogen atom, an alkyl group, an allyl group, a cyclic ester group, a non-cyclic ester group, a cyclic ether group, and an non-cyclic ether group. A denotes a complex cycle. N is 1 or 2, and R may be identical or different when n is 2.

Journal ArticleDOI
TL;DR: A new ether lipid core (designated as FU) was found in Methanothermus fervidus total lipid and the structure of FU was suggested to be a modified caldarchaeol in which two hydrocarbon chains are bridged with a covalent bond.

Journal ArticleDOI
TL;DR: In this article, a new methodology for the synthesis of (E)-3-benzylidenechroman-4-ones using methyl 3-aryl-3-hydroxy-2-methylenepropanoates, derived from methyl acrylate, is described.

Journal ArticleDOI
TL;DR: In this paper, photochromic dithienylethene having two benzo-12-crown-4 ethers and bis(benzothienyl)ethene with two crown ether moieties of the open ring form captured large metal ions cooperatively like tweezers, while the photogenerated closed-ring form released the ions.
Abstract: Alkali metal ion extraction was carried out using photochromic dithienylethene having two benzo-12-crown-4 ethers (1), benzo-15-crown-5 ethers (2), or benzo-18-crown-6 ethers moieties (3) and bis(benzothienyl)ethene having two benzo-18-crown-6 ether moieties (4) Two crown ether moieties of the open-ring form captured large metal ions cooperatively like tweezers, while the photogenerated closed-ring form released the ions The reduced affinities for metal picrates were fully recovered by irradiation with visible light (>480 nm) The 1H NMR spectrum measurement of the solutions (CDCl3/CD3CN: 5/1) containing both alkali metal picrates and 2 or 3 confirmed that the large alkali metal ions were captured by the two intramolecular crown ethers

Journal ArticleDOI
TL;DR: In this paper, two-dimensional (2D) chemical-transport modeling of the atmospheric lifetimes of dimethyl ether and fluorinated ethers CH 3 OCF 3 (E143a), CHF 2 OCHF 2 (E134), and CH F 2 OCF3 (E125) is presented.
Abstract: Using recent kinetic data, two-dimensional (2-D) chemical-transport modeling of the atmospheric lifetimes of dimethyl ether and fluorinated ethers CH 3 OCF 3 (E143a), CHF 2 OCHF 2 (E134), and CHF 2 OCF 3 (E125) shows that E134 and E125 have substantially larger lifetimes than previously estimated. Dimethyl ether has a short atmospheric lifetime of 5.1 days and a relatively insignificant radiative forcing leading to a relatively low global warming potential. Increasing fluorination is accompanied by slower rates of reaction with hydroxyl radical and ultimately longer lifetimes. E143a, E134, and E125 were found to have lifetimes of 5.7, 29.7, and 165 years, respectively. In addition, our work uses ah initio methodology to determine IR absorption cross sections for each ether. Our study finds that E134 and E125 have significant infrared absorption and thus relatively high radiative forcing values. Thcse two propertics together yield global warming potentials for E134 and E125 of 5720 and 14,000, respectively, integrated over a 100 year period.

Journal ArticleDOI
TL;DR: In this article, a three-flask protocol was proposed to synthesize six-nine-membered cyclic enol ethers from pendant carbonyls and olefins.
Abstract: Fused heterocyclic ring systems are the key skeletal arrangement in a vast array of bioactive natural products. The family of compounds which best illustrate this structural feature are the marine “ladder” toxins whose skeletons include cisand trans-fused six-nine-membered oxygenated heterocycles. Although the members of this family are most commonly associated with neurotoxicity and “red tide” catastrophes,1 some have shown potent antimicrobial activity and lack neurotoxicity (cf. gambieric acid).2,3 The very interesting bioactivity of the members of this family when coupled with their molecular complexity would seem to warrant an efficient approach to their synthesis and/or to the synthesis of analogues if they are to be fully evaluated.4 With this in mind, the regularity in these structures has influenced many, including us, to believe that an iterative strategy to the fused ether skeleton would be ideal. While independent investigations from the laboratories of Mori,5 Clark,6,7 McDonald,8 and Martin9 approach this ideal, to date there exist no general iterative strategies to synthesize sixnine-membered cyclic ethers. At the outset, we envisioned a novel three-flask protocol toward fused ether ring systems. This strategy centered around stereoselective cyclic enol ether epoxidations and subsequent epoxide opening reactions with carbon nucleophiles (1 f 3, Scheme 1).10-13 While the epoxidation of C-3 substituted glycals appeared to be fairly well understood,10,14,15 the lack of information regarding the stereoselective epoxidation of C-3 unsubstituted glycals as well as more complex ring systems (biand tricyclic enol ethers, medium sized rings) was a concern. Despite this, we decided to pursue this approach because of the considerable flexibility provided by the existence of a large number of epoxidation protocols (vide infra). After C-C bond formation, annulation would result in a new cyclic enol ether and thus complete the iterative pathway (cf. 3 f 4, Scheme 1). Among the many possible methods that had the potential to meet our cyclization needs, carbonyl-olefin and olefinolefin metathesis chemistry were particularly attractive as they were capable of generating cyclic enol ethers from pendant carbonyls and olefins.16,17 Additionally, these methods of ring formation have been used in the synthesis of fused ethers.6,7,18-21 Described herein are our preliminary experiments in this area which utilize the paradigm illustrated in Scheme 1.

Journal ArticleDOI
TL;DR: In this paper, Li2(TripBen)ZrMe2 and B(C6F5)3 in pentane yields colorless crystals of (Trip-Ben)(CD3)2 revealing that π bonding between boron and nitrogen results in one Trip ring on each borone being oriented over the two alkyl groups.

Journal ArticleDOI
TL;DR: In this article, the luminescence properties of divalent europium complexes with crown ether, azacrown ether, N-pivot-azacrown- ether, and cryptand in methanol or water have been systematically investigated under UV irradiation.

Journal ArticleDOI
TL;DR: The 1,2-bis(4,4′-dipyridinium)ethane dication threads through dibenzo-24-crown ether (DB24C8) to form a pseudorotaxane which is easily stoppered to form [2]rotaxanes either by alkylation or coordination of a transition metal complex as discussed by the authors.

Journal ArticleDOI
TL;DR: Salinomycin, a commercially significant coccidiostat isolated from Streptomyces albus, has been synthesised from three principal fragments as discussed by the authors, including the use of η3-allylmolybdenum cationic complexes 21a,b for the stereoselective construction of two contiguous stereogenic centres in fragment 5a; (b) the electrophilic cyclisation of 2-(prop-2-ynyl)-2-hydroxyoxanes to give molybenum and chromium carbene complexes which are precursors
Abstract: Salinomycin, a commercially significant coccidiostat isolated from Streptomyces albus, has been synthesised from three principal fragments. Key steps include (a) the use of η3-allylmolybdenum cationic complexes 21a,b for the stereoselective construction of two contiguous stereogenic centres in fragment 5a; (b) the electrophilic cyclisation of 2-(prop-2-ynyl)-2-hydroxyoxanes to give molybdenum and chromium carbene complexes which are precursors to the furan fragment 7; (c) the diastereoselective oxidation of a 1,5-diene with potassium permanganate to generate four stereogenic centres in a single step leading to fragment 8; (d) the oxidative rearrangement of acylfuran 89 en route to the 1,6,8-trioxadispiro[4.1.5.3]pentadec-13-ene dispiroacetal core; and finally (e) the use of an allenol ether as an acyl anion equivalent together with the stereoselective hydrolysis of allenol ether intermediate 112 in an alternative synthesis of the dispiroacetal core.

Journal ArticleDOI
TL;DR: In this article, the thermally-induced and photo-induced polymerization of the electron-donating divinyl ether di(4-vinyloxybutyl)succinate (DVBS) and the electron accepting 1,5-bis(maleimido)-2-methylpentane (BMMP) and their monofunctional analogues, dodecylvinyl ether (DDVE), N-methylmaleimide (NMM), and N-phenylmaleimides (NPM).
Abstract: We report on the thermally-induced and photoinduced polymerization of the electron-donating divinyl ether di(4-vinyloxybutyl)succinate (DVBS) and the electron accepting 1,5-bis(maleimido)-2-methylpentane (BMMP) and their monofunctional analogues, dodecylvinyl ether (DDVE), N-methylmaleimide (NMM), and N-phenylmaleimide (NPM). We focus on the stoichiometry of the monomer constituents consumed in the polymerization and the structural identity and bonding configuration(s) of the polymer products. For both BMMP−DVBS and NMM−DDVE, FTIR and 1H NMR data indicate 1:1 stoichiometry for the resulting polymer. For both systems, the polymers are of the alternating donor and acceptor form (DA)n. This result holds for both photoinduced and thermally induced reactions. Structural NMR studies of polymers synthesized from both mono- and difunctional monomers indicate the presence of both cis and trans conformers of the acceptor at the D−A bond. This finding indicates that thermodynamic factors alone are not sufficient to ...

Journal ArticleDOI
TL;DR: In this paper, the micellar structure of PAA-g-PS in toluene has been demonstrated by dynamic light scattering and transmission electron microscopy (TEM).
Abstract: An amphiphilic poly(acrylic acid)/polystyrene graft copolymer (PAA-g-PS) has been used to form “nanoreactors” for the synthesis of gold clusters. Such copolymers tend to form stable micelles in non-polar organic solvents where the poly(acrylic acid) chains constitute the core, and the polystyrene chains, the shell. In the present study, the micellar structure of PAA-g-PS in toluene has been demonstrated by dynamic light scattering and transmission electron microscopy (TEM). The subsequent preparation of gold-graft copolymer composites involved the introduction of gold chloride (AuCl3), either in powder form or previously dissolved in ether, into the micellar cores of the PAA-g-PS in toluene. The gold salt was then reduced by ultraviolet (UV) irradiation of the emulsion, or of dried cast films. TEM and ultraviolet-visible (UV/Vis) spectroscopy were used to characterize the resulting composites. Gold particles of less than 5 nm in diameter were observed in all cases, but the size distribution and the spatial arrangement of the clusters in the cast films were modified when diethyl ether was used to introduce AuCl3 into the PAA-g-PS micellar cores. This was thought to be due to enhanced nucleation of the gold particles and partial disruption of the micellar cores in the presence of diethyl ether.

Journal ArticleDOI
TL;DR: In this article, the size of the encapsulated cation determines which product is formed, i.e., a crown ether, a dimeric crown ether or a sandwich complex.
Abstract: Metallacoronates or metallacrown ether sandwich complexes? As with organocrown ethers, the size of the encapsulated cation (Na+, Ca2+, or K+) determines which product is formed—a crown ether, a dimeric crown ether, or a sandwich complex (see below). H2L = ketipinate.

Journal ArticleDOI
TL;DR: In this paper, a new azacrown ether derived from 1,8-naphthalimide was prepared by a two-step reaction from 4-bromo-1,8 naphthalic anhydride.

Journal ArticleDOI
TL;DR: A review of friction and wear studies of poly(ether ether ketone) (PEEK) blended with other polymers is presented in this paper, where a number of investigations into the tribology of PEEK blended with poly(PEI), polytetrafluoroethylene (PTFE) and liquid crystalline polymers (LCPs) have been reported.

Journal ArticleDOI
TL;DR: In this article, a chiral copper carbenoid with the oxygen atom of a pendant allylic ether was obtained using a copper complex of the enantiomerically pure diimine 1a.

Journal ArticleDOI
TL;DR: Friedel-Crafts acylation of aromatic ethers with acid anhydrides in the presence of mesoporous material, cation-exchanged K10 montmorillonite (M n + - mont., where M n + =Fe 3+, Zn 2+, Cu 2+, Al 3+ and Co 2+ ) was investigated as mentioned in this paper.
Abstract: Friedel–Crafts acylation of aromatic ethers with acid anhydrides in the presence of mesoporous material, cation-exchanged K10 montmorillonite (M n + – mont., where M n + =Fe 3+ , Zn 2+ , Cu 2+ , Al 3+ and Co 2+ ) was investigated. Fe 3+ - and Zn 2+ -exchanged montmorillonites displayed higher activities ascribed to the synergistic effect of Bronsted and Lewis acidities. Selective acylation is a significant achievement with the formation of 1-acyl-2-methoxynaphthalene, 4-acyl anisole and 4-acyl veratrole from respective aromatic ethers.