30314-46-6Relevant academic research and scientific papers
FLUORINE-CONTAINING COMPOUND, SUBSTRATE FOR PATTERN FORMATION, PHOTODEGRADABLE COUPLING AGENT, PATTERN FORMATION METHOD, AND COMPOUND
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Paragraph 0159-0164, (2017/06/27)
A compound represented by formula (e): where R1 represents a branched chain or cyclic alkyl group having 3 to 10 carbon atoms, and Rf1 and Rf2 represent fluorinated alkoxy groups.
Substituent effects at the benzyl position and aromatic ring of silane-coupling agents containing 2-nitrobenzyl esters on photosensitivity and hydrophobic surface of a self-assembled monolayer (SAM)
Konishi, Tsubasa,Hashimoto, Teppei,Sato, Naoya,Nakajima, Kazuki,Yamaguchi, Kazuo
, p. 125 - 134 (2016/01/27)
Silane-coupling agents with 2-nitrobenzyl esters containing alkyl substituents at the benzyl position and alkoxy and/or fluoroalkoxy groups of the aromatic ring were synthesized to prepare a self-assembled monolayer (SAM) on quartz glass, silicon wafer and thermally oxidized silicon wafer. The resulting photosensitive SAMs before and after photoirradiation were characterized by contact angle measurement, UV spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray reflectivity (XRR). Photosensitivity of the SAM was influenced by substituents at the benzyl position and aromatic ring as well as the irradiation conditions in air or solution and substrates employed. Silane-coupling agents with bulky substituent at the benzyl position and double fluoroalkoxy chains are preferable in terms of the photosensitivity and hydrophobic surface.
Friedel-Crafts acylation using bismuth triflate in [BMI][PF6]
Tran, Phuong Hoang,Duus, Fritz,Le, Thach Ngoc
experimental part, p. 222 - 224 (2012/01/30)
Bismuth trifluoromethanesulfonate was found to be a good catalyst for the Friedel-Crafts acylation. Bismuth triflate immobilized in an ionic liquid was the most efficient catalytic system. Bismuth triflate in [BMI][PF6] catalyzes this reaction under microwave irradiation allowing the rapid synthesis of aryl ketones in excellent yields. The catalyst system was easily recovered and reused several times.
Aerobic Oxidation of Benzyl Alcohols Catalyzed by Aryl Substituted N-Hydroxyphthalimides. Possible Involvement of a Charge-Transfer Complex
Annunziatini, Claudia,Gerini, Maria Francesca,Lanzalunga, Osvaldo,Lucarini, Marco
, p. 3431 - 3438 (2007/10/03)
A series of aryl-substituted N-hydroxyphthalimides (X-NHPIs) containing either electron-withdrawing groups (4-CH3OCO, 3-F) or electron-donating groups (4-CH3, 4-CH8O, 3-CH 3O, 3,6-(CH3O)2) have been used as catalysts in the aerobic oxidation of primary and secondary benzylic alcohols. The selective formation of aromatic aldehydes was observed in the oxidation of primary alcohols; aromatic ketones were the exclusive products in the oxidation of secondary alcohols. O-H bond dissociation enthalpies (BDEs) of X-NHPIs have been determined by using the EPR radical equilibration technique. BDEs increase with increasing the electron-withdrawing properties of the aryl substituent. Kinetic isotope effect studies and the increase of the substrate oxidation rate by increasing the electron-withdrawing power of the NHPI aryl substituent indicate a rate-determining benzylic hydrogen atom transfer (HAT) from the alcohol to the aryl-substituted phthalimide-N-oxyl radical (X-PINO). Besides enthalpic effects, polar effects also play a role in the HAT process, as shown by the negative ρ values of the Hammett correlation with σ + and by the decrease of the ρ values (from -0.54 to -0.70) by increasing the electron-withdrawing properties of the NHPI aryl substituent. The relative reactivity of 3-CH3O-C6H4CH 2OH and 3,4-(CH3O)2-C6H3CH 2OH, which is higher than expected on the basis of the σ + values, the small values of relative reactivity of primary vs secondary benzylic alcohols, and the decrease of the ρ values by increasing the electron-withdrawing properties of the NHPI aryl substituent, suggest that the HAT process takes place inside a charge-transfer (CT) complex formed by the X-PINO and the benzylic alcohol.
Promoting laccase activity towards non-phenolic substrates: A mechanistic investigation with some laccase-mediator systems
Baiocco, Paola,Barreca, Anna Maria,Fabbrini, Maura,Galli, Carlo,Gentili, Patrizia
, p. 191 - 197 (2007/10/03)
The oxidation of benzyl alcohols with the enzyme laccase, under mediation by appropriate mediator compounds, yields carbonylic products, whereas laccase can not oxidise these non-phenolic substrates directly. The oxidation step is performed by the oxidised form of the mediator (Medox), generated on its interaction with laccase. The Medox can follow either an electron transfer (ET) or a radical hydrogen atom transfer (HAT) route of oxidation of the substrates. Experimental evidence is reported that enables unambiguous assessment of the occurrence of either one the oxidation routes with each of the investigated mediators, namely, ABTS, HBT, HPI and VLA. Support to the conclusions is provided by (i) investigating the intermolecular selectivity of oxidation with appropriate substrates, (ii) attempting Hammett correlations for the oxidation of a series of 4-X-substituted benzyl alcohols, (iii) measuring the kinetic isotope effect, (iv) investigating the product pattern with suitable probe precursors. Based on these points, a HAT mechanism results to be followed by the laccase-HBT, laccase-HPI and laccase-VLA systems, whereas an ET route appears feasible in the case of the laccase-ABTS system.
Lifetime, reduction potential and base-induced fragmentation of the veratryl alcohol radical cation in aqueous solution. Pulse radiolysis studies on a ligninase "Mediator"
Bietti, Massimo,Baciocchi, Enrico,Steenken, Steen
, p. 7337 - 7342 (2007/10/03)
The radical cation of veratryl alcohol (3,4-dimethoxybenzyl alcohol), VA?+, was produced in aqueous solution, mainly by oxidation with the radiation chemically generated SO4?- or Tl2+. By electron-transfer equilibration with thioanisole as a redox standard, the reduction potential of VA?+ was determined to be 1.36 ± 0.01 V/NHE. On the basis of product analysis results, the radical cation undergoes a C - H deprotonation reaction from the side chain, leading to an α-hydroxybenzyl-type radical, with k = (17 ± 1) s-1 at pH ≤ 5, as determined by time-resolved conductance. The α-hydroxybenzyl-type radical was also produced by reduction of veratryl aldehyde with the hydrated electron, and the pKa value of this radical was determined to be 10.0. The deprotonation of VA?+ is enhanced by bases such as OH-, with the rate constant being 1.3 × 109 M-1 s-1. In contrast, the corresponding rate constant for reaction of OH with the radical cation of veratryl alcohol methyl ether, whose reduction potential is also 1.36 V/NHE, is only 2 × 107 M-1 s-1. With the veratryl alcohol derivative, 3,4-(MeO)2C6H3CH(OH)CMe3, the radical cation undergoes both a proton loss from the benzylic position and a Cα-Cβ fragmentation with the ratio, at pH ≤ 5, of ca. 1:2. The decay of the radical cation is strongly enhanced by OH (k = 8.3 × 109 M-1 s-1), with the base induction favoring the C-C fragmentation relative to the proton loss from the benzylic position. The possible bearing of these results with respect to the role of VA in the lignin peroxidase-catalyzed decomposition of lignin is discussed.
The catalytic Friedel-Crafts acylation reaction of aromatic compounds with carboxylic anhydrides using combined catalyst system of titanium(IV) chloride tris(trifluoromethanesulfonate) and trifluoromethanesulfonic acid
Izumi, Jun,Mukaiyama, Teruaki
, p. 739 - 740 (2007/10/03)
Various aromatic ketones are prepared in good to high yields with carboxylic anhydrides using combined catalyst system of TiCl(OTf)3 and TfOH.
