Jun 16, 2011 ... Pure compounds (either as the free phenols, the methyl ether, or the methyl ether-acetate derivatives) were isolated by a variety of ...
Treesearch
... Abstract : Polyacetals, owing to the acid sensitivity of the acetal linkage, are attractive candidates for end uses in which acid sensitivity is a desirable ...
DTIC Science & Technology
Trifluoromethanesulfonic acid catalyzed isomerization of kinetic enol derivatives to the thermodynamically favored isomers was developed. Under the present conditions, kinetic enol phosphates, enol acetates and benzoates, and enol sulfonates were smoothly isomerized to produce the corresponding thermodynamically favored isomers in good ...
PubMed
Lewis acid catalyzed inverse-electron-demand Diels-Alder reaction of tropone derivatives was developed. Up to 97% ee was obtained for the chiral dinucleus BINOL-aluminum complex catalyzed reaction between tropones and ketene diethyl acetal to give bicyclo[3.2.2] ring structures, which opens up a unique way of making chiral ...
A Br�nsted acid-catalyzed Prins-type cyclization sequence to construct spirooxindole pyrans in high yields and excellent diastereoselectivity has been developed. The combination of a ?-hydroxy dioxinone fragment and isatin dimethyl acetal generate oxa-spirooxindoles efficiently. These compounds are diversifiable scaffolds that tap into the rich chemistry ...
Acetic acid (AA)-catalyzed liquid hot water (LHW) pretreatments on raw corn stover (RCS) were carried out at 195 degrees C at 15 min with the acetic acid concentrations between 0 and 400 g/kg RCS. After pretreatment, the liquor fractions and water-insoluble solids (WIS) were collected separately and tested in terms of the recoveries of glucan and xylan ...
Hydrothermal kinetics experiments indicate that acetate decomposes under achievable hydrothermal conditions dependant upon solution pH and the catalytic and/or oxidizing ability of mineral surfaces present. Surfaces studied thus far include quartz, calcit...
National Technical Information Service (NTIS)
A kind of porous carbon spheres (PCS) was prepared by the carbonization of poly(vinylidene chloride) synthesized by suspension polymerization. Structure analyses revealed the existence of bumps and holes on the surface of PCS. The PCS, with the pore size between 0.8-1.2 nm, could be used as the support of zinc acetate because of the regular shape, high specific surface area, ...
NASA Astrophysics Data System (ADS)
We have studied the reaction selectivities of acid catalyzed ring opening reactions of epoxidized methyl oleate (methyl 9,10-epoxy stearate; EMO), to form either acetal or branched ester products. We have produced: methyl 9-(2-butyl-2-methyl-5-octyl-1,3-dioxolan-4-yl) nonanoate (hexanone methyl st...
Technology Transfer Automated Retrieval System (TEKTRAN)
4-Oxoalkanal dimethyl 1-acetals are obtained with an overall yield of 60-85% by the action of 1-bromo-2-ethoxycyclopropyllithium on methyl carboxylates, acid-catalyzed methanolysis of the obtained 1-bromo-2-ethoxycyclopropyl ketones, and subsequent treatment of the reaction mass with zinc powder or triphenylphosphine.
Energy Citations Database
1,2-cis-Glycosyl acetates with the ?-configuration were revealed to be very unreactive towards Lewis acid catalyzed thioglycosylations. Optimal and cost-effective conditions for enabling this direct conversion is absent in the literature. Our studies have shown that elevating the reaction temperature with a catalytic amount of ...
An efficient two-step route to a broad range of aza- and diazaindoles was established, starting from chloroamino-N-heterocycles, without the need for protecting groups. The method involves an optimized Suzuki-Miyaura coupling with (2-ethoxyvinyl)borolane followed by acetic acid-catalyzed cyclization. PMID:19950955
Contents: Acid-catalyzed hydrolysis of isopropylidene acetals of some 2-pentuloses and 2-hexuloses; Improved preparation of 1,2:3,4-di-O-isopropylidene-D-erythro-pentulofuranose; Conformational analysis of heterocyclic compounds, p-dioxane-2,3-diol; Studi...
Polyacetals, owing to the acid sensitivity of the acetal linkage, are attractive candidates for end uses in which acid sensitivity is a desirable property, e.g. photo- or electron-resists. Many polysaccharides belong to this general class and owe many of ...
The H-D exchange reactions of p-deuterated anisole and thioanisole and of mono-deuterated benzene were investigated in acetic acid containing sulfuric acid as catalyst. Anisole was found to react 30 to 40 times faster than thioanisole, and thioansole in turn reacts 50 times faster than benzene. (D.L.C.)
This paper uses ESR and V 51 NMR spectroscopy to study possible intermediates in the disproportionation of H/sub 2/O/sub 2/ in 1-2% aqueous acetic acid in the presence of vanadium complexes. The intermediate formation of vanadium (5+) peroxo complexes was detected under conditions of the disproportionation of hydrogen peroxide in acetic ...
The first catalytic asymmetric method to prepare enantioenriched N,S-acetals using chiral BINOL phosphoric acids is reported. The reaction combines N-acyl imines with thiols to generate products in excellent yield and enantioselectivity. The addition reaction could also be achieved with an exceptional substrate to catalyst (S/C) molar ratio. Electron-rich and ...
... Accession Number : ADD403994. Title : Mechanism of acid catalyzed reaction of amines with epoxides. Corporate Author ...
that it is not simply a Lewis acid catalyzed decomposition by the aluminum ..... Lewis acid-catalyzed dispropor- tionation reaction mechanism (ref. 21). ...
NASA Website
Hydrothermal kinetics experiments indicate that acetate decomposes under achievable hydrothermal conditions dependant upon solution pH and the catalytic and/or oxidizing ability of mineral surfaces present. Surfaces studied thus far include quartz, calcite, pyrite, Ca-montmorillonite, iron-bearing montmorillonite, magnetite, and ...
The presentation gives an overview of some recent advances in our research on hydrothermal conversion of biomasses, mainly including cellulose and lignocellulosic biomass, and carbon dioxide into chemicals, such as acetic acid, lactic acid and formic acid.
This paper describes a newly developed acetal-based positive tone deep UV photoresist called DX 46. The material consists of a 4-hydroxystyrene/4-hydroxy-3-methylstyrene copolymer, a polymeric dissolution inhibitor, and a bleachable diazo-photoactive compound. Each of the three compounds is specially designed to fit to each other for high performance sub-halfmicron resolution. ...
By-products were formed on analysis of beta-muricholic acid (3 alpha, 6 beta, 7 beta-trihydroxy-5 beta-cholan-24-oic acid) in biological samples by a method involving acid-catalyzed solvolysis of sulfate esters in acetone-methanol, followed by perchloric acid-catalyzed acetylation with acetic anhydride-acetic acid. ...
Pseudo-first-order rate constants and catalytic rate constants are reported for the buffer-catalyzed hydrolysis of 4-fluoroquinaldine (1) in carboxylic acid and phosphoric acid buffers. The buffer catalysis is consistent with specific acid, general base catalysis. Hydrolyses in 99% /sup 18/O-labeled acetate, indicate that the predominant catalytic mode for the ...
The present work pertains to the study of the influence of nickel, cobalt, thorium, vanadium, molybdate, ferrous ions on the formation of cysteine which is synthesized abiogenically together with other amino acids in sterilized aqueous mixtures of ammonium thiocyanate, formaldehyde, potassium dihydrogen phosphate, calcium acetate, and biological minerals after irradiating by ...
A very efficient three-component synthesis of a series of syn ?-hydroxy-?-amino esters, obtained in high diastereoselection and yield, was realized starting from an aldehyde, benzylamine, and the ketene silyl acetals derived from Ley's lactones. The synthetic protocol was optimized and the above compounds were obtained without the isolation of intermediates. The origin of the ...
Acid-catalyzed cyclization of 1-O-cis-alk-1'-enyl-sn-glycerol produced four structurally and geometrically isomeric long-chain cyclic acetals of glycerol. The isomers were isolated by adsorption and gas-liquid chromatography and were identified as cis-2-alkyl-5-hydroxy-1,3-dioxane (Ia), trans-2-alkyl-5-hydroxy-1,3-dioxane (IIa), ...
We have created a two-week, two hour-per-week cyclic experiment, which pairs two reactions. These reactions, the acid catalyzed esterification to yield n-amyl acetate and the base catalyzed hydrolysis of n-amyl acetate are intended to serve as a first and last experiment respectively, of the second-semester ...
This report describes a new a continuous method for forming ethers, acetals and ketals using solid acid catalysts, DELOXAN ASP or AMBERLYST 15, and supercritical fluid solvents. In the case of ether formation, the authors observe a high selectivity for linear alkyl ethers with little rearrangement to give branches ethers. Such rearrangement is common in conventional synthesis. ...
This paper studies the decomposition of peracetic acid (AcOOH) in acetic acid (AcOH) catalyzed by vanadium complexes. It is shown that peractic acid in acetic acid solutions of ammonium anadate decomposes with the predominant formation of 0/sub 2/ and small amounts of CO/sub 2/, the yield of which increases with increasing temperature and peracetic acid ...
The principle of chemical amplification has proven to be successful for the design of highly sensitive, high resolution resist materials of both positive and negative tone, respectively. This paper discusses our new approach to a high resolution, aqueous base developable deep-UV negative tone resist. It is based on the acid catalyzed cleavage of ...
Glyoxal and methyl glyoxal (G+MG) are secondary pollutants produced by the atmospheric oxidation of aromatic compounds, isoprene and terpenes. They are known to partition efficiently into tropospheric water droplets, reaching micromolar concentrations. While G+MG hydrates are quite unreactive, we show that cloud droplet evaporation triggers accretion acid-catalyzed reactions ...
... Abstract : NMR spectra of monomethylol urea and acid catalyzed solutions of ... be composed of residues of compound 2-keto-5-carboxyamide-1,3,-5 ...
The sulfuric acid catalyzed dehydration of 1,1'-diadamantyl-methylcarbinol in anhydrous acetic acid proceeds exclusively to 1,1'-bis(1-adamantyl)ethylene. The secondary deuterium isotope effect of 1.32 found for this reaction shows that carbonium ion formation from the protonated alcohol is rate determining. In the ...
A two-step hydrothermal process to improve the production of acetic acid was discussed. The first step was to accelerate the formation of 5-hydroxymethyl-2-furaldehyde (HMF), 2-furaldehyde (2-FA), and lactic acid (LA), and the second step was to further convert the furans (HMF, 2-FA) and LA produced in the first step to acetic acid by ...
Inexpensive and readily available sulfonic acids, p-toluenesulfonic acid, and sulfuric acid are versatile and efficient catalysts for the peracetylation of a broad spectrum of carbohydrate substrates in good yield and in a practical time frame. Three appealing features in sulfonic acid-catalyzed acetylation of free sugars were explored including (1) suppression of furanosyl ...
The exchange between molecular hydrogen and D/sub 2/O is known to be eatalyzed by hydroxide ion and follows the rate law/sup 3/d(P/sub HD/)/dt lambda k(P/sub H2/)(OH/sup -/). The exchange has been investigated at lower pH values in the temperature range ll0 to 190 deg using borate, phosphate, glycine, succinate and acetate buffers. The same rate law is obeyed ...
Oxidation of phenols by isoquinolinium bromochromate (IQBC) in aqueous acetic acid leads to the formation of corresponding quinones. The reaction is first order with respect to both phenol and IQBC and catalysed by hydrogen ion. The rate of oxidation decreases with increase in dielectric constant of solvent indicating ion-dipole interaction. The rate of oxidation decreases ...
The reactions of the ring-contracted aldehydes, derived from anhydrodihydroartemisinin, with gem-difluoroenoxysilanes in the presence of BF(3).Et(2)O afforded the corresponding difluoromethylene ketol adducts in good yields. Similar Lewis acid catalyzed reactions of dihydroartemisinin acetate with the difluoroenoxysilanes provided the ...
[reaction: see text] Carbamates or sulfonamides have proven to regioselectively attack 2-propynyl-allyl hybrid cations, generated by the action of TMSOTf on 4-(trimethylsioxy)hex-5-en-2-ynoates, to afford conjugated 6-aminohex-4-en-2-ynoates in which an intramolecular amino-Michael reaction took place, leading to pyrrole frameworks. In particular, the sulfonamides gave 1-sulfonylpyrroles in one ...
Previous work by Wasserman and co-workers showed that 2,7-dioxabicyclo-[2.21]heptanes can be formed via a thermal of Lewis acid-catalyzed rearrangement of 3,4-epoxy ketones. The author utilized this keto-epoxide rearrangement in the approach to the synthesis of nemorensic acid. A novel reaction of Grignard reagents with bicyclic acetals was developed ...
Effect of various hydrothermal pretreatments [at different temperatures (400-800{degrees}C) and concentrations of steam (13-80 mol%) or with liquid water at 150{degrees}C under autogenous pressure] to H-gallosilicate (MFI) zeolite (bulk Si/Ga = 33 and Na/Ga = 0.1) on its acidity/acid strength distribution (determined by chemisorption and step-wise thermal desorption of ...
Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, we examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. We also examine products from the subsequent ...
Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. They also examined products from ...
DOE Information Bridge
The partial oxidation of 4-tert-butyltoluene to 4-tert-butylbenzaldehyde by hydrogen peroxide in glacial acetic acid, catalyzed by bromide ions in combination with cobalt(II) acetate or cerium(III) acetate, has been studied in detail. Based on the observed differences in reaction rates and ...
The reduction of carbon dioxide (CO(2)) under mild hydrothermal conditions was carried out in the presence of iron nanoparticles. In this reaction system, the iron nanoparticles not only act as the reducing agent but also catalyze the reduction of CO(2) to form formic acid and acetic acid. PMID:20104858
To prepare abrasion-resistant antireflective (AR) films for inertial confinement fusion, four solgel routes have been investigated on polysiloxane-modified and polyvinylalcohol- (PVA-) modified SiO{sub 2} sols. As confirmed with a transmissive electron microscope, different fractal structure characteristics of the modified SiO{sub 2} particles are disclosed by small-angle x-ray scattering ...
To prepare abrasion-resistant antireflective (AR) films for inertial confinement fusion, four solgel routes have been investigated on polysiloxane-modified and polyvinylalcohol- (PVA-) modified SiO2 sols. As confirmed with a transmissive electron microscope, different fractal structure characteristics of the modified SiO2 particles are disclosed by small-angle x-ray scattering technology. And it ...
Lewis acid-catalyzed cyclization of aminoacetals 2 and triethyl ethenetricarboxylate (1a) has been examined. The reaction of 3-aminopropionaldehyde diethyl acetal (2a) and 1a in the presence of 1 equiv of TiCl(4) at room temperature gave 4-ethoxypiperidine-2,3,3-tricarboxylate 3a in 92% yield with a 2,4-diastereomer ratio of 1:1. The reaction in the ...
A series of tribenzotriquinacene derivatives bearing three oxy-functionalised alkyl groups at the benzhydrylic bridgeheads (C-4b, C-8b and C-12b) have been synthesised. The 4b,8b,12b-triallyl derivative was used to generate the corresponding TBTQ-tris-acetaldehyde and TBTQ-tris(acetic acid), in which the functional groups stretch out from the convex rigid molecular surface. ...
The hydrolysis of many ortho esters, and some acetals and ketals, is general acid catalyzed, and in some examples these generate linear Bronsted plots over substantial ranges of catalyst acidity. This suggests that the reaction coordinate is primarily a reorganization of heavy atoms since proton transfer from one oxygen to another has ...
Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. The authors also examine products ...
A thermally stable, vanadium-containing silicate with the MEL structure has been prepared by hydrothermal crystallization. XRD and framework IR spectra of samples with three different Si/V ratios suggest the presence of V ions in framework positions wherein the concentration of SiOH groups is likely to be high. ESR spectra of the as-synthesized and reduced samples indicate ...
Solutions of zinc(II) acetate in acetic acid/sodium acetate buffer solutions of varying concentration were examined by X-ray absorption spectroscopy (XAS) at temperatures between 25 and 200 �C. The influence on speciation by increasing the ratio of available acetate to Zn concentration was marked, and followed a ...
A new process for producing calcium acetate, a non-corrosive deicer, is proposed. The process consists of a two-step continuous-flow hydrothermal conversion of vegetable wastes into acetic acid and the production of calcium acetate, followed by the separation and condensation of the product. The experiments for ...
As a renewable non-food resource, lignocellulosic biomass has great potential as an energy source or feedstock for further conversion. However, challenges exist with supply logistics of this geographically scattered and perishable resource. Hydrothermal carbonization treats any kind of biomass in 200 to 260�C compressed water under an inert atmosphere to produce a ...
A Lewis acid-catalyzed rearrangement of phosphorimidates allows a direct, high-yielding transformation of azides with commercially available phosphites into secondary phosphoramidates. PMID:18566729
Lewis acids catalyze the cyclization of methyl phenyldiazoacetates with an ortho-imino group, prepared from o-aminophenylacetic acid, to give 2,3-substituted indoles in quantitative yields. PMID:19904905
Lewis acids catalyze the cyclization of methyl phenyldiazoacetates with an ortho-imino group, prepared from o-aminophenylacetic acid, to give 2,3-substituted indoles in quantitative yields.
PubMed Central
An efficient acid-catalyzed sulfetherification of various unsaturated alcohols with sulfenamides to form tetrahydrofurans and tetrahydropyrans regioselectively is described. Mechanistic studies have shown that the tetrahydrofurans can stereoselectively rearrange to the corresponding tetrahydropyrans. PMID:21361303
Title: Acid catalyzed reactions of alpha and beta styryl azides. Online Source: Click to View PDF File [PDF Size: 427 KB]. Author: Boyer, J. H.; Krueger, ...
... Title : Fluorescence Quenching of Methoxybenzyl Alcohols by the Hydronium Ion in Aqueous Solution: Acid-Catalyzed Formation of Methoxybenzyl ...
... Accession Number : ADA095669. Title : Aromatic Substitution. 43. Perfluorinated Resinsulfonic Acid Catalyzed Nitration of Aromatics,. ...
... There is some evidence to suggest thatsecondary alcohols tend to dehydrate more rapidly than primary alcoholsduring acid catalyzed esterification ...
Primary kinetic isotope effects (KIEs) on a series of carboxylic acid-catalyzed protonation reactions of aryl-substituted alpha-methoxystyrenes (X-1) to form oxocarbenium ions have been computed using the second-order Kleinert variational perturbation theory (KP2) in the framework of Feynman path integrals (PI) along with the potential energy surface obtained at the ...
Primary kinetic isotope effects (KIEs) on a series of carboxylic acid-catalyzed protonation reactions of aryl-substituted ?-methoxystyrenes (X-1) to form oxocarbenium ions have been computed using the Kleinert variational second-order perturbation theory (KP2) in the framework of Feynman path integrals (PI) along with the potential energy surface obtained at the ...
Lewis acid or Br�nsted acid catalyzed reactions of vinylidene cyclopropanes (VDCPs), 1, with activated carbon-nitrogen, nitrogen-nitrogen, and iodine-nitrogen double-bond-containing compounds have been thoroughly investigated. We found that pyrrolidine and 1,2,3,4-tetrahydroquinoline derivatives can be formed in good yields in the reactions of VDCPs 1 ...
Acid-catalyzed 1-octene reactions with phenol and mixtures of phenol with water, acetic acid and 1-butanol were studied as partial bio-oil upgrading models. Bio-oil from fast biomass pyrolysis has poor fuel properties due to the presence of substantial amounts of water, carboxylic acid, phenolic derivatives and other hydroxyl-containing compounds. ...
Atmospheric Environment 40 (2006) 6863�6878 Acid-catalyzed reactions of hexanal on sulfuric acid are incorporated into atmospheric aerosols are not well understood. Acid-catalyzed reactions of compounds into acidic aerosols. In the present study, we use the aerodyne aerosol mass spectrometer (AMS) to probe
E-print Network
This study aimed to produce acetic acid from vegetable wastes by a new hydrothermal two-step process. A continuous flow reaction system with a maximum treatment capacity of 2 kg/h of dry biomass developed by us was used. Five kinds of vegetables of carrots, white radish, chinese cabbage, cabbage and potato were selected as the representation of vegetable ...
The production of formic acid and acetic acid by hydrothermal oxidation of alkali lignin, a kind of biomasses, was investigated using a batch reactor with H2O2 oxidant. Experiments were performed over a wide range of conditions with temperature varying from 260 to 320� C, oxygen supply varying from 60% to 120%, and reaction time varying from 30 to 150 s. ...
The authors compared the activity of acetyl-CoA-synthetase and of the enzymes belonging to the group of asparaginic acid in levomycetin sensitive and resistant strains of Y. pestis and E. coli. There were revealed marked differences in the activity of aspartase, fumarase, synthetase and desamidase of L-asparagin, and also of the enzyme activated by acetate in the E. coli ...
Herein is reported the first laboratory observation of the oligomerization of levoglucosan studied under atmospherically relevant conditions. Oligomers up to 1458 Da (9-mer) were measured by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. A rational mechanism is proposed based on both the acid-catalyzed cationic ring-opening of levoglucosan and nucleophilic attack of ...
Taxol 1, a novel anticancer agent, isolated from Taxus brevifolia, is a member of the class of taxane diterpenes. Since its isolation and characterization many groups around the world using varied approaches have made significant contributions toward the assembly of the taxane framework and ultimately to taxol itself. The focus of this investigation was directed towards making a fully ...
1,2-Cyclopropaneacetylated sugars as glycosyl donors reacted with a series of glycosyl acceptors (monosaccharides, amino acids, and other alcohols) in the presence of Lewis acid to produce oligosaccharides and glycoconjugates containing 2-C-acetylmethylsugars. Galactosyl donor gave good to excellent ?-selectivities with TMSOTf as a catalyst, whereas galactosyl donor offered moderate to good ...
Bagasse was liquefied in ethylene glycol (EG) catalyzed by sulfuric acid at 190 degrees C under atmospheric pressure. The compositions of the crude products obtained were analyzed after separating them into three fractions: a water-soluble fraction, an acetone-soluble fraction and a residue. With infrared, gel permeation chromatography and elemental analyses, the residue mainly included ...
Protective group-free syntheses of four racemic pheromones with a 6,8-dioxabicyclo[3.2.1]octane ring were achieved in five or six steps from commercially available (�)-3-butyn-2-ol (6) and 2-alkenyl halides or 2-alken-1-ol by employing Lewis acid-catalyzed acetalization of ?, ?-epoxy ketones as the key reaction. (�)-Frontalin (1) was prepared in a 25% ...
This paper presents the progress we have made toward the development of fully water processable, negative and positive tone I-line resist systems. The negative tone system is based on styrene copolymers bearing pendant ammonium sulfonate groups and vicinal diol functionalities. The salt provides the means of rendering the polymer water soluble. The diol undergoes an acid ...
Lewis acid-catalyzed dimerization of mono- and disaccharidic per-O-acetylated glycals gave di- and tetrasaccharidic O-acetylated C-glycosides, respectively. 2,3-Enopyranosyl cyanides were obtained from per-O-acetylated glycals by a new, mild anomeric S(N)'-acetoxy displacement with Hg(CN)(2)/HgBr(2)/TMSCN. Per-O-acetylated 2-C-2-deoxy-pyranoses were converted into pyranosyl ...
Recent environmental chamber studies have suggested that acid-catalyzed particle-phase reactions of organic carbonyls lead to multifold increases in secondary organic aerosol (SOA) mass and acid-catalyzed reactions between alcohols and aldehydes in the condensed phase lead to the formation of hemiacetals and acetals, also enhancing secondary organic aerosol growth. The ...
Chiral Cu(I)-bisoxazoline- and Cu(I)-PN-complexes were found to catalyze the intermolecular insertion of alpha-diazo compounds into N-H bonds. The insertion reactions proceed with enantioselectivities of up to 28% ee for the different alpha-diazo acetates into one of the N-H bonds of different amines. Analogous chiral Ag(I) complexes were found to give higher ...
We have prepare several novel silicon-containing polymers containing both low Ea and high Ea protecting groups, and we have evaluated these materials at both 193 nm. Low Ea acetal-containing polymers were prepared by reacting poly(4-vinylphenol) with novel silyl enol ethers. The ease of protecting group cleavage in these materials is manifested in the immediate formation of a ...
New acetal or ketal blocking reagents were investigated for use in e-beam lithography and compared with the performance of ethyl vinyl either (EVE). Three blocking groups, (alpha) -Angelicalactone (AL), 6-methylene-5,6-benzo-1,4- dioxane (MBD), and MANA50 (an undisclosed blocking group used to show the potential of this chemistry) were reacted with poly(p-hydroxystyrene) (PHS) ...