Catalysis-chemistry

Le Vaillant, Franck published the artcileRoom temperature decarboxylative cyanation of carboxylic acids using photoredox catalysis and cyanobenziodoxolones: a divergent mechanism compared to alkynylation, Synthetic Route of 1798-04-5, the publication is Chemical Science (2017), 8(3), 1790-1800, database is CAplus and MEDLINE.

The one-step conversion of aliphatic carboxylic acids to the corresponding nitriles was accomplished via the merger of visible light mediated photoredox and s (CBX) reagents. The reaction proceeded in high yields with natural and non-natural ¦Á-amino and ¦Á-oxy acids, affording a broad scope of nitriles with excellent tolerance of the substituents in the ¦Á position. The direct cyanation of dipeptides and drug precursors was also achieved. The mechanism of the decarboxylative cyanation was investigated both computationally and exptl. and compared with the previously developed alkynylation reaction. Alkynylation was found to favor direct radical addition, whereas further oxidation by CBX to a carbocation and cyanide addition appeared more favorable for cyanation. A concerted mechanism was proposed for the reaction of radicals with EBX reagents, in contrast to the usually assumed addition elimination process.

Chemical Science published new progress about 1798-04-5. 1798-04-5 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ether, name is 2-(4-(tert-Butyl)phenoxy)acetic acid, and the molecular formula is C12H16O3, Synthetic Route of 1798-04-5.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Wu, T. C. published the artcileAddition of silylmetallic compounds to olefins, COA of Formula: C12H10F2Si, the publication is Journal of Organic Chemistry (1960), 596-8, database is CAplus.

Ph₃SiK (I) and Ph₃SiLi (II) added to the olefinic linkage of 1,1-diphenylethylene (III) and of triphenylethylene (IV). No addition occurred, under corresponding conditions, to tetraphenylethylene (V) and to a variety of aliphatic and alicyclic olefins. For comparison purposes, triphenyl(1,1-diphenylethyl)silane (VI) and triphenyl(1,1,2-triphenylethyl)silane (VII) were synthesized by metalation of triphenyl(diphenylmethyl)silane (VIII) with BuLi and subsequent treatment with Me₂SO₄ and PhCH₂Cl (IX), resp. I suspension (from cleavage of 0.01 mole hexaphenyldisilane) left 2 hrs. with 3.6 g. III in 20 ml. Et₂O, the mixture hydrolyzed, the solution dried, and Et₂O evaporated gave 3.5 g. triphenyl(2,2-diphenylethyl)silane (X), lustrous plates, m. 106-8¡ã (alc.). II (0.0122 mole) in tetrahydrofuran (THF) added to 2.2 g. III, the mixture stirred 0.5 hr. at room temperature, then hydrolyzed, the organic layer evaporated, and the residue recrystallized gave 80% X. Ph₂CHCH₂Cl (4.3 g.) in 20 ml. Et₂O added during 2 min. to an amalgamated suspension of 0.02 mole I, the mixture left 2 hrs., hydrolyzed, and the product isolated gave 1.1 g. hexaphenyldisilane. The Et₂O solution on evaporation gave 4.1 g. X. PhLi (0.002 mole) in THF added to 0.5 g. triphenyl-¦Â-styrylsilane, stirred 2 hrs. at room temperature, the mixture hydrolyzed, Et₂O added, the solvent removed, and the residue chromatographed on Al₂O₃ gave 0.18 g. Ph₄Si. No other product was isolated from the mother liquor. BuLi (0.015 mole) added at once to 5 g. VIII in 25 ml. THF, the solution stirred 40 min. at room temperature, excess Me₂SO₄ added, then hydrolyzed, and the product separated gave 58% VI, m. 193-5¡ã (C₆H₆-alc.). II (0.020 mole) in THF added to 5.12 g. IV, the mixture stirred 1 hr. at room temperature, hydrolyzed, and the organic layer worked up as usual gave 6.4 g. 1,2,2-isomer of VII, m. 171-2¡ã (C₆H₆-alc.). BuLi (0.015 mole) added to 5 g. VIII in 25 ml. THF, stirred 40 min. at room temperature, excess IX added, the mixture hydrolyzed, and worked up gave 1.5 g. VII, m. 198-200¡ã (C₆H₆-alc.). II (0.015 mole) in THF stirred 6 hrs. at room temperature with 5 g. V, then 1 hr. at 50¡ã, hydrolyzed with dilute acid, and the organic portion worked up gave 4.2 g. V, m. 222-4¡ã; the filtrate chromatographed gave 2.2 g. Ph₃SiH, m. 43-5¡ã (MeOH). Attempted reactions of I with other olefins were carried out by mixing a suspension of I with an equimolar amount of the olefinic compound; the mixture stirred a certain time, H₂O added, the organic layer dried, evaporated, and the residue crystallized gave triphenylsilanol (XI) as chief product. In 2 experiments with 1,2-dimethoxyethane as the solvent, a mixture of V and hexaphenyldisiloxane was also obtained. In the reaction of 9,9′-bifluorene with I in Et₂O, heat was evolved and the mixture became dark. The workup gave a tarlike material from which little pure product could be isolated. The following results were obtained with I (olefin, reaction time in hrs., % yield of XI, and other products isolated given): 1-octene, 96, 63, -; 1-octene, 48, 25, 24% Ph₄Si, 22% (R₃Si)₂O (XII); 1-dodecene, 72, 78, -; 1-dodecene, 48, 21, 36% R₄Si, 20% XII; 1-hexadecene, 24, 86, -; 1-octadecene, 24, 89, -; cyclohexene, 48, 87, -; cyclohexene, 48, 66, -; 1-methylcyclopentene, 48, 72, -; 1,1-diphenylethylene, 2, -, 42% adduct; V, 48, 74, 70% R₂C:CR₂; V, 3, 52, 74% R₂C:CR₂; 1,4-diphenyl-1,3-butadiene, 5, 42, 12% (R₃Si)₂; 9,9′-bifluorene, 3, -, tar.

Journal of Organic Chemistry published new progress about 312-40-3. 312-40-3 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Difluorodiphenylsilane, and the molecular formula is C3H5F3O, COA of Formula: C12H10F2Si.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Koch, Alexander published the artcileHydrocarbon-soluble bis(trimethylsilylmethyl)calcium and calcium-iodine exchange reactions at sp²-hybridized carbon atoms, SDS of cas: 1206-46-8, the publication is Organometallics (2017), 36(20), 3981-3986, database is CAplus.

Hydrocarbon-soluble and highly reactive [(L)_xCa(CH₂SiMe₃)₂] (2a, L = tetrahydropyran, x = 4; 2b,L = tmeda, x = 2) are synthesized by the metathesis reaction of Me₃SiCH₂CaI (1-I) with KCH₂SiMe₃. The stability of 2a in tetrahydropyran solution at 0¡ã is sufficiently high for subsequent chem. transformations. The reaction of ICH₂SiMe₃ with calcium in di-Et ether yields unique iodide-bridged cage compound [Ca₃(¦Ì₃-I)(¦Ì-I)₃(¦Ì₃-OEt)(CH₂SiMe₃)(OEt₂)₅] (3). We demonstrate that alkylcalcium complexes are valuable reagents for calcium-iodine exchange reactions at C_sp2-I functionalities.

Organometallics published new progress about 1206-46-8. 1206-46-8 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Trimethyl(perfluorophenyl)silane, and the molecular formula is C9H9F5Si, SDS of cas: 1206-46-8.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Heil, Moritz published the artcileCharacterization of Gun Propellants by Long-term Mass Loss Measurements, Synthetic Route of 1821-27-8, the publication is Propellants, Explosives, Pyrotechnics (2017), 42(7), 706-711, database is CAplus.

A review. Three different gun propellants (A5020, JA-2 or L5460, NK1074) have been investigated up to 35 years by mass loss at isothermal temperatures between 30¡ãC and 90¡ãC. From these data, activation energies for the different reactions of zero order (mass loss increase up to stabilizer consumption) and first order (solvent evaporation at begin) are derived. The mass loss data are described very well by a combination of these two reactions. Stabilizer consumption has been determined by HPLC. In case of diphenylamine (DPA), several consecutive products (mononitro-DPA up to tetranitro-DPA) have been regarded also. Activation energies are in the range of energies obtained by other methods: 84 kJ/mol [A5020], 150 kJ/mol [JA-2], 100 kJ/mol [NK 1074]. Long term measurements show seasonal influence in the mass loss data. Resp. graphs are shown in this work. At least four years of measurement are recommended to compensate for the signal drift caused by seasonal changes.

Propellants, Explosives, Pyrotechnics published new progress about 1821-27-8. 1821-27-8 belongs to catalysis-chemistry, auxiliary class Nitro Compound,Amine,Benzene, name is Bis(4-nitrophenyl)amine, and the molecular formula is C12H9N3O4, Synthetic Route of 1821-27-8.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Uddin, Jashim Md. published the artcileDiscovery of Furanone-Based Radiopharmaceuticals for Diagnostic Targeting of COX-1 in Ovarian Cancer, Safety of Tetrabutylammonium hydrogencarbonate, the publication is ACS Omega (2019), 4(5), 9251-9261, database is CAplus and MEDLINE.

In vivo targeting and visualization of cyclooxygenase-1 (COX-1) using multimodal positron emission tomog./computed tomog. imaging represents a unique opportunity for early detection and/or therapeutic evaluation of ovarian cancer because overexpression of COX-1 has been characterized as a pathol. hallmark of the initiation and progression of this disease. The furanone core is a common building block of many synthetic and natural products that exhibit a wide range of biol. activities. We hypothesize that furanone-based COX-1 inhibitors can be designed as imaging agents for the early detection, delineation of tumor margin, and evaluation of treatment response of ovarian cancer. We report the discovery of 3-(4-fluorophenyl)-5,5-dimethyl-4-(p-tolyl)furan-2(5H)-one (FDF), a furanone-based novel COX-1-selective inhibitor that exhibits adequate in vivo stability, plasma half-life, and pharmacokinetic properties for use as an imaging agent. We describe a novel synthetic scheme in which a Lewis acid-catalyzed nucleophilic aromatic deiodo[¹⁸F]fluorination reaction is utilized for the radiosynthesis of [¹⁸F]FDF. [¹⁸F]FDF binds efficiently to COX-1 in vivo and enables sensitive detection of ovarian cancer in s.c. and peritoneal xenograft models in mice. These results provide the proof of principle for COX-1-targeted imaging of ovarian cancer and identify [¹⁸F]FDF as a promising lead compound for further preclin. and clin. development.

ACS Omega published new progress about 17351-62-1. 17351-62-1 belongs to catalysis-chemistry, auxiliary class Salt,Amine, name is Tetrabutylammonium hydrogencarbonate, and the molecular formula is C13H11NO, Safety of Tetrabutylammonium hydrogencarbonate.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Gee, J. C. published the artcileKinetics of hydrogen peroxide oxidation of alkyl dimethyl amines, Application In Synthesis of 28056-87-3, the publication is Journal of the American Oil Chemists’ Society (1997), 74(1), 65-67, database is CAplus.

We measured the absolute rate constants for the hydrogen peroxide oxidation of two different octyl di-Me amines in isopropanol/water mixtures at 23¡ã. The amines were 1-octyl di-Me amine (1) and 2-ethylhexyl di-Me amine (2); their structures were analogous to those most often encountered in com. alkyl di-Me amine oxide production The observed first-order rate constants for the disappearance of amine across a range of H₂O₂ concentrations (0.5-8 M) indicated that the overall rate was first-order in amine and 3/2-order in H₂O₂. Calculations showed k₁ = 0.16 M^-1h^-1, k₂ = 0.046 M^-1h^-1, and k₁/k₂ = 3.5. The rates appeared to decrease with increasing steric hindrance around the nitrogen atom. We also investigated the effect of water on the reaction rates. When [H₂O] < ?4.5 M in isopropanol, the rates increased with increasing [H₂O]; for [H₂O] > ?4.5 M, the rates were insensitive to [H₂O].

Journal of the American Oil Chemists’ Society published new progress about 28056-87-3. 28056-87-3 belongs to catalysis-chemistry, auxiliary class Amine,Aliphatic hydrocarbon chain, name is 2-Ethyl-N,N-dimethylhexan-1-amine, and the molecular formula is C10H23N, Application In Synthesis of 28056-87-3.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Ricigliano, Vincent A. published the artcileEffects of different artificial diets on commercial honey bee colony performance, health biomarkers, and gut microbiota, HPLC of Formula: 63-68-3, the publication is BMC Veterinary Research (2022), 18(1), 52, database is CAplus and MEDLINE.

Honey bee colonies managed for agricultural pollination are highly dependent on human inputs, especially for disease control and supplemental nutrition. Hives are routinely fed artificial “pollen substitute” diets to compensate for insufficient nutritional forage in the environment. The aim of this study was to investigate the effects of different artificial diets in a northern California, US com. beekeeping operation from August through Feb. This time period represents an extended forage dearth when supplemental nutrition is used to stimulate late winter colony growth prior to almond pollination in the early spring. A total of 144 honey bee colonies were divided into 8 feeding groups that were replicated at three apiary sites. Feeding groups received com. diets (Global, Ultra Bee, Bulk Soft, MegaBee, AP23, Healthy Bees), a beekeeper-formulated diet (Homebrew), or a sugar neg. control. Diets were analyzed for macronutrient and amino acid content then evaluated with respect to honey bee colony population size, average bee weight, nutrition-related gene expression, gut microbiota abundance, and pathogen levels. Replicated at three apiary sites, two pollen-containing diets (Global and Homebrew) produced the largest colonies and the heaviest bees per colony. Two diets (Bulk Soft and AP23) that did not contain pollen led to significantly larger colonies than a sugar neg. control diet. Diet macronutrient content was not correlated with colony size or health biomarkers. The sum of dietary essential amino acid deficiencies relative to leucine content were correlated with average bee weight in Nov. and colony size used for almond pollination in Feb. Nutrition-related gene expression, gut microbiota, and pathogen levels were influenced by apiary site, which overrode some diet effects. Regarding microbiota, diet had a significant impact on the abundance of Bifidobacterium and Gilliamella and trended towards effects on other prominent bee gut taxa. Multiple colony and individual bee measures are necessary to test diet efficacy since honey bee nutritional responses are complex to evaluate. Balancing essential amino acid content relative to leucine instead of tryptophan may improve diet protein efficiency ratios. Optimization of bee diets could improve feed sustainability and agricultural pollination efficiency by supporting larger, healthier honey bee colonies.

BMC Veterinary Research published new progress about 63-68-3. 63-68-3 belongs to catalysis-chemistry, auxiliary class Natural product, name is (S)-2-Amino-4-(methylthio)butanoic acid, and the molecular formula is C5H11NO2S, HPLC of Formula: 63-68-3.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Tam, Shuk Ching published the artcileElectrostatic interactions between organic ions, Computed Properties of 10517-44-9, the publication is Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases (1984), 80(8), 2255-67, database is CAplus.

Association constants of organic cations and anions with different charge separations, rigidity, and shapes were determined and compared with association constants of inorganic cations with organic anions and of inorganic anions with inorganic cations. Bjerrum’s theory of ion-pair formation is applicable to spherical inorganic ions, but not to ions having anisotropic charge distributions and shapes. For the latter, charge matching is an important factor in the association and is most effective for rigid ions.

Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases published new progress about 10517-44-9. 10517-44-9 belongs to catalysis-chemistry, auxiliary class Salt,Amine,Aliphatic hydrocarbon chain, name is Propane-1,3-diamine dihydrochloride, and the molecular formula is C8H13NO3, Computed Properties of 10517-44-9.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Fuerstenau, D. W. published the artcileThe effect of non-equilibrium adsorption at the solid-vapor interface on the recedence of aqueous films and dewetting of solid surfaces, Safety of Dodecylamineacetate, the publication is Colloids and Surfaces, A: Physicochemical and Engineering Aspects (1994), 89(2/3), 205-12, database is CAplus.

Phenomena involving the recedence of relatively thick films were investigated in the paraffin-water and Pyrex-dodecylammonium acetate-water systems. Non-equilibrium adsorption was found to enhance the dewetting or recedence velocity of aqueous films from the surface of Pyrex glass. An explanation, based on the enhanced zipper-like adsorption at the solid-vapor interface as the liquid-vapor interface is destroyed, is presented to explain in existence of a maximum recedence velocity. These effects are absent in the paraffin-water system. This work reflects recedence behavior in practical non-quiescent systems.

Colloids and Surfaces, A: Physicochemical and Engineering Aspects published new progress about 2016-56-0. 2016-56-0 belongs to catalysis-chemistry, auxiliary class Active Esterification, name is Dodecylamineacetate, and the molecular formula is C14H31NO2, Safety of Dodecylamineacetate.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Fuerstenau, D. W. published the artcileThe recedence of thick aqueous films in the dewetting of solid surfaces, Application of Dodecylamineacetate, the publication is Colloids and Surfaces, A: Physicochemical and Engineering Aspects (1994), 89(2/3), 193-204, database is CAplus.

The recedence of relatively thick aqueous films from flat solid surfaces was investigated exptl. for two different substrates: paraffin wax and polished Pyrex glass. The wettability of Pyrex was controlled by the addition of dodecylammonium acetate. Using the conservation of energy principle, a model was developed to analyze steady state recedence velocity in terms of the surface free energy change, kinetic energy of the receding liquid, friction loss, kinetic energy loss and gravitational potential energy of the system. A numerical solution of the model was utilized and compared with the exptl. data. The model indicates an insensitivity to viscous dissipation and corroborates not only the thermodn. theory for film recedence, but also the general conceptions of other workers on film movement.

Colloids and Surfaces, A: Physicochemical and Engineering Aspects published new progress about 2016-56-0. 2016-56-0 belongs to catalysis-chemistry, auxiliary class Active Esterification, name is Dodecylamineacetate, and the molecular formula is C14H31NO2, Application of Dodecylamineacetate.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia