79-02-7Relevant academic research and scientific papers
Ensemble effects in nanostructured TiO2 used in the gas-phase photooxidation of trichloroethylene
Yeung,Maira,Ho,Wei,Stolz,Soria,Chao,Hung,Yue
, p. 4608 - 4616 (2002)
The effects of crystal size, structure, and crystallinity on the photocatalytic activity of nanostructured TiO2 with different crystal sizes (3, 5, and 6 nm) for the gas-phase heterogeneous photocatalytic oxidation of trichloroethylene (TCE) wa
Some Transformations of Mono-and Dichloro(diethoxyphosphoryl)acetaldehydes
Allakhverdieva, G. E.,Ismailov, V. M.,Mamedov, I. A.,Sadykhova, N. D.,Yusubov, N. N.
, p. 89 - 92 (2020/04/09)
Addition of ethanol and diethyl phosphonate to the carbonyl group of 2,2-dichloro-2-(diethoxyphosphoryl)-acetaldehyde has been studied, and the corresponding α-chloro ether, acetal, and phosphorylated metrifonate have been obtained. α,α-Dichloro-α-phospho
Tricyclic base analogues
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, (2008/06/13)
Nucleoside analogues have structure (2) wherein Q is H or a sugar moiety or sugar analogue or a modified sugar or a nucleic backbone or backbone analogue, W is an alkylene or alkenylene chain of 0-5 carbon atoms, any of which may carry a substituent R8, X is O or N or NR12or CR10, X′ is O or S or N, provided that when X′ is O or S, then X is C, Y is CH or N, R6is NH2or SMe or SO2Me or NHNH2, each of R7and R8is independently H or F or alkyl or alkenyl or aryl or acyl or a reporter moiety, R12is independently H or alkyl or alkenyl or aryl or acyl or a reporter moiety, and R10is H or ═O or F or alkyl or aryl or a reporter moiety.
Evidence for an additional oxidant in the photoassisted Fenton reaction
Pignatello, Joseph J.,Liu, Di,Huston, Patrick
, p. 1832 - 1839 (2007/10/03)
The photo-Fenton reaction (Fe3+ + H2O2 + UV) has potential applications in wastewater treatment. This reaction was compared to H2O2 photolysis and other reactions that produce only hydroxyl radicals (OH·) in order to probe for additional or alternative intermediates that may contribute to the recognized potency of photo-Fenton as an oxidant of organic compounds. Distinct differences were found between photo-Fenton and genuine OH· reactions. The kinetic deuterium isotope effect (KDIE) for cyclohexane in the photo-Fenton reaction increases from 1.2 to 1.4 with increasing concentration of OH· scavenger, tert-butyl alcohol; whereas the KDIE in genuine OH· reactions (H2O2/UV, Fe3+/UV, and Fe2+ + H2O2) is 1.1 and unchanged in the presence of tert-butyl alcohol. Photo-Fenton catalyzed the epoxidation of cyclohexene at a much greater rate than H2O2/UV. The relative yields of chlorinated organic acids from 1,1,2-trichloroethane, trichloroethene, and tetrachloroethene oxidation were markedly affected by the presence of iron. Time-resolved laser flash photolysis spectroscopy in the absence of organics revealed a transient, seen only in Fe3+ + H2O2 solutions, with broad absorbance in the visible and a lifetime of ~100 ns. The results suggest the participation of a high-valent oxoiron complex (ferryl) in addition to OH· in organic compound oxidations. Hydrogen peroxide forms a complex with iron, Fe(O2H)2+ (K15 = 1.15 x 10-2), that absorbs in the visible region and could be the precursor of the ferryl complex. The photo-Fenton reaction (Fe3+ + H2O2 + UV) has potential applications in wastewater treatment. This reaction was compared to H2O2 photolysis and other reactions that produce only hydroxyl radicals (OH·) in order to probe for additional or alternative intermediates that may contribute to the recognized potency of photo-Fenton as an oxidant of organic compounds. Distinct differences were found between photo-Fenton and genuine OH· reactions. The kinetic deuterium isotope effect (KDIE) for cyclohexane in the photo-Fenton reaction increases from 1.2 to 1.4 with increasing concentration of OH· scavenger, tert-butyl alcohol; whereas the KDIE in genuine OH· reactions (H2O2/UV, Fe3+/UV, and Fe2+ + H2O2) is 1.1 and unchanged in the presence of tert-butyl alcohol. Photo-Fenton catalyzed the epoxidation of cyclohexene at a much greater rate than H2O2/UV. The relative yields of chlorinated organic acids from 1,1,2-trichloroethane, trichloroethene, and tetrachloroethene oxidation were markedly affected by the presence of iron. Time-resolved laser flash photolysis spectroscopy in the absence of organics revealed a transient, seen only in Fe3+ + H2O2 solutions, with broad absorbance in the visible and a lifetime of approx. 100 ns. The results suggest the participation of a high-valent oxoiron complex (ferryl) in addition to OH· in organic compound oxidations. Hydrogen peroxide forms a complex with iron, Fe(O2H)2+ (K15 = 1.15 × 10-2), that absorbs in the visible region and could be the precursor of the ferryl complex.
α-(Acyloxy)dialkylnitrosamines: Effects of structure on the formation of N-nitrosiminium ions and a predicted change in mechanism
Hongliang, Cai,Fishbein, James C.
, p. 1826 - 1833 (2007/10/03)
The decay of α-(acyloxy)dialkylnitrosamines in aqueous solutions has been studied with a view toward elucidating mechanistic details and effects of structure on mechanism and reactivity. Rate constants (k1) for the pH-independent decay of 43 α-(acyloxy)dialkylnitrosamines have been determined. Observations from these and other experiments rule out decomposition via an anchimeric assistance mechanism involving the Z isomer that had previously been suggested. All of the reported data for most of the compounds is consistent with a mechanism involving the formation of N-nitrosiminium ions in or before the rate-limiting step. Structure -reactivity correlations indicate that the stability of α-(acyloxy)dialkylnitrosamines is determined by electronic properties of substituents at RN and RC as well as by the ability of substituents RC to engage in hyperconjugative interactions of C-H bonds with the developing cationic center in the transition state for nitrosiminium ion formation. Attachment of substituents of sufficient electron-withdrawing power at RN and RC results in a predicted change in mechanism to what appears to be an acyl group attack mechanism.
Process for the hydroxyalkylation of a carbocyclic aromatic ether
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, (2008/06/13)
The present invention concerns a process for the hydroxyalkylation of a carbocyclic aromatic ether. The invention preferably relates to the preparation of 3-methoxy-4-hydroxybenzyl alcohol by the hydroxymethylation of guaiacol. It also concerns the oxidation of the hydroxyalkylated ethers obtained, in particular the oxidation of 3-methoxy-4-hydroxybenzyl alcohol to 3-methoxy-4-hydroxybenzaldehyde, commonly known as "vanillin". The process for the hydroxyalkylation of a carbocyclic aromatic ether of the invention consists of reacting the aromatic ether with a carbonyl compound in the presence of a catalyst and is characterized in that the hydroxyalkylation reaction is carried out in the presence of an effective quantity of a zeolite.
Some reactions of ammonia and primary amines with propanal, 2-chloroethanal, 2,2-dichloroethanal and 2,2,2-trichloroethanal in acetonitrile
Crampton, Michael R.,Lord, Simon D.,Millar, Ross
, p. 909 - 914 (2007/10/03)
The reaction of ammonia with propanal in acetonitrile produces the hexahydrotriazine, 1, in good yield. The corresponding reaction of chloroethanal yields the cyclic trimer 16 but only in poor yield. Increasing chloro-substitution in the aldehyde stabilises the initially formed carbinolamines and disfavours trimerisation. Imines formed by reaction of primary amines with the aldehydes are relatively stable. Those formed from aliphatic amines may undergo slow dimerisation by C-C bond formation and this may be accompanied by loss of amine to yield products containing a conjugated double-bond system. Kinetic and equilibrium data are reported for both the forward and reverse reactions involving interconversion of propanal and ammonia with 1 in acetonitrile-water mixtures. The results indicate that dehydration of the carbinolamine is rate determining.
Pharmaceutical composition for inhibiting HIV protease
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, (2008/06/13)
A pharmaceutical composition is disclosed which comprises a solution of an HIV protease inhibiting compound in a pharmaceutically acceptable organic solvent comprising a mixture of (1) (a) a solvent selected from propylene glycol and polyethylene glycol or (b) a solvent selected from polyoxyethyleneglycerol triricinoleate, polyethylene glycol 40 hydrogenated castor oil, fractionated coconut oil, polyoxyethylene (20) sorbitan monooleate and 2-(2-ethoxyethoxy)ethanol or (c) a mixture thereof and (2) ethanol or propylene glycol.
Pharmaceutical composition
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, (2008/06/13)
A solid pharmaceutical composition is disclosed which comprises a pharmaceutically acceptable adsorbent or a mixture of pharmaceutically acceptable adsorbents to which is adsorbed a mixture of (1) a pharmaceutically acceptable organic solvent or a mixture of pharmaceutically acceptable organic solvents, (2) an HIV protease inhibiting compound and (3) one or more pharmaceutically acceptable acids. The solid composition can optionally be encapsulated in a hard gelatin capsule.
Reactions of α-Chloro- and α,α-dichloro-β-oxoaldehydes with Anionic Nucleophiles
Guseinov, F. I.,Tagiev, S. Sh.,Moskva, V. V.
, p. 86 - 89 (2007/10/03)
The reaction of α-chloro and α,α-dichloro-β-oxoaldehydes with anionic nucleophiles (NaOH, MeONa, PhONa, MeCOOK) proceeds mainly via haloform splitting with elimination of the formyl group; only with the most nucleophilic sodium methoxide, the reaction at the β-carbon atom partially occurs.The intermediate anions react with benzaldehyde to give difficulty accessible polyfunctional compounds.
