Month: November 2022

Shermolovich, Yu. G. published the artcileReaction of N-alkyl- and N-(arylsulfonyl)sulfinimidic acid chlorides with triphenylphosphine, HPLC of Formula: 19117-31-8, the publication is Zhurnal Organicheskoi Khimii (1991), 27(10), 2245-6, database is CAplus.

Reaction of ArSCl:NBu-tert [Ar = (un)substituted Ph] with PPh₃ afforded aminyl radicals ArSN^?Bu-tert + Ph₃PCl₂. ArSCl:NSO₂Ar’ (Ar, Ar’ as above) underwent transimidation with PPh₃, affording Ph₃P:NSO₂Ar’.

Zhurnal Organicheskoi Khimii published new progress about 19117-31-8. 19117-31-8 belongs to catalysis-chemistry, auxiliary class Oxidant, name is N-(tert-Butyl)-S-phenylthiohydroxylamine, and the molecular formula is C9H7NO4, HPLC of Formula: 19117-31-8.

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

Huang, Dejian published the artcileFacile and Reversible Cleavage of C-F Bonds. Contrasting Thermodynamic Selectivity for Ru-CF₂H vs F-Os:CFH, Application of Trimethyl(perfluorophenyl)silane, the publication is Journal of the American Chemical Society (2000), 122(37), 8916-8931, database is CAplus.

In the presence of a catalytic amount of F^– (CsF), Me₃SiR_f (R_f = CF₃ and C₆F₅) exchanges R_f with fluoride of the 16-electron complexes MHF(CO)L₂ (M = Ru, Os; L = PⁱPr₃, P^tBu₂Me) to give Me₃Si-F and the unsaturated pentafluorophenyl complexes, MH(C₆F₅)(CO)L₂, or (when R_f = CF₃) saturated fluorocarbene complexes, MHF(CF₂)(CO)L₂, via ¦Á-F migration. X-ray crystal structure and solution ¹⁹F NMR studies reveal that, in the ground state, the three atoms of the CF₂ group lie in a plane perpendicular to the P-Ru-P axis so that the ¦Ð-back-donation is maximized and the carbene substituents are inequivalent. Having hydride trans to the CF₂ ligand, MHF(CF₂)(CO)L₂ is a kinetic product, which converts to a thermodn. isomer. For Ru, the final product is a 16e complex, RuF(CF₂H)(CO)L₂, formed by combination of CF₂ and hydride. For Os, the product is an 18e complex, OsF₂(:CFH)(CO)L₂, resulting from exchange of one carbene fluoride with the hydride. The distinct difference between Os and Ru demonstrates the principle that 3rd-row transition metals show a pronounced tendency toward a higher oxidation state. The isomerization mechanism involves phosphine dissociation as a slow step. Coordinatively saturated RuHF(CF₂)(CO)L₂ reacts with CO within the time of mixing to give the F and CF₂ recombination product, RuH(CF₃)(CO)₂L₂. This unexpectedly fast carbonylation reaction, as well as ¹⁹F spin saturation transfer experiments, reveals the existence of a fast ¦Á-F migration equilibrium between RuHF(CF₂)(CO)L₂ and RuH(CF₃)(CO)L₂ in solution In sharp contrast, the Os analog does not have such a fast equilibrium, and therefore it does not react with CO at room temperature At higher temperature, reaction occurs forming the hydride and fluoride exchanged product, Os(CHF₂)(F)(CO)₂L₂. The contrasting behavior of Ru vs. Os regarding stability of fluoroalkyl and fluorocarbene is discussed on the basis of the theor. calculations, which also provide insight into the isomerization of RuHF(CF₂)(CO)L₂. Hydrogenolysis of Ru(CF₂H)F(CO)L₂ liberates CH₂F₂, forming RuHF(CO)L₂.

Journal of the American Chemical Society 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, Application of Trimethyl(perfluorophenyl)silane.

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

Lastovickova, Lenka published the artcileDried blood spot as an alternative sample for screening of fatty acid, amino acid, and keto acid metabolism in humans, HPLC of Formula: 6217-54-5, the publication is Biomedical Chromatography (2022), 36(9), e5431, database is CAplus and MEDLINE.

Dried blood spot (DBS) is a simple and noninvasive sample collection technique allowing self-collection at home. It can be used as an alternative sample for the screening of metabolism in humans because changes in the levels of some fatty acids (FAs), amino acids (AAs), and keto acids (KAs) can be associated with metabolic disorders (e.g., diabetes mellitus). In this study, we optimized three different methods that are sensitive enough for the determination of the aforementioned analytes from a small volume of biol. material in DBS. A total of 20 AAs, 5 KAs, and 24 FAs were determined This sampling technique was applied to prepare samples from 60 individuals by a finger prick. The samples were analyzed using chromatog. methods, and acquired data were statistically evaluated. Even though most analytes were higher in men, only five AAs, three KAs, and eight FAs showed significant gender dependency (¦Á = 0.05). Asparagine, serine, and ¦Á- and ¦Ã-linolenic acids showed significant age dependency (¦Á = 0.05). Most statistically significant correlations were pos. and were found within one category. This work shows that because of many benefits, the DBS sample could be a good alternative to whole blood sample collection for the screening of metabolism in humans, in general, or in individualized medicine. The chromatog. methods can be used in future research, for example, to set the reference range or plasma-correction factors (various aspects such as age or gender should be considered).

Biomedical Chromatography published new progress about 6217-54-5. 6217-54-5 belongs to catalysis-chemistry, auxiliary class Alkenyl,Carboxylic acid,Aliphatic hydrocarbon chain,Metabolic Enzyme,RAR/RXR,Natural product, name is Docosahexaenoic Acid, and the molecular formula is C22H32O2, HPLC of Formula: 6217-54-5.

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

Hsu, I-Nan published the artcileDissociation constants of four disubstituted cinnamic acids, Safety of (E)-3-(2,4-Dimethoxyphenyl)acrylic acid, the publication is Journal of the Indian Chemical Society (1967), 44(6), 540-1, database is CAplus.

The apparent pK values of trans-2,3-dimethoxycinnamic acid, trans-2,4-dimethoxycinnamic acid, trans-3,4-dimethoxycinnamic acid, and trans-3,5-dimethoxycinnamic acid were calculated at various concentrations, and extrapolation to a bulk concentration of 0 gives pK 4.37 ¡À 0.03, 4.80 ¡À 0.03, 4.53 ¡À 0.03, and 4.36 ¡À 0.003, resp. It is assumed that the activity coefficient of the undissociated acid is unity. Inductive and mesomeric effects are discussed.

Journal of the Indian Chemical Society published new progress about 16909-09-4. 16909-09-4 belongs to catalysis-chemistry, auxiliary class Alkenyl,Carboxylic acid,Benzene,Ether, name is (E)-3-(2,4-Dimethoxyphenyl)acrylic acid, and the molecular formula is C11H12O4, Safety of (E)-3-(2,4-Dimethoxyphenyl)acrylic acid.

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

Flapper, Jitte published the artcileNickel and Palladium Complexes of New Pyridine-Phosphine Ligands and Their Use in Ethene Oligomerization, Application of Dimesitylphosphine oxide, the publication is Organometallics (2009), 28(11), 3272-3281, database is CAplus.

New pyridine-phosphine ligands of general structure 2-[2-(diarylphosphino)ethyl]pyridine were developed. The phosphorus substituents in these bidentates are 2-tolyl, 2-anisyl, and mesityl. The ligands could be conveniently synthesized in good yields. The nickel dichloride complexes of the ligands are paramagnetic. The metal centers have a distorted tetrahedral geometry, as was evident from the crystal structures and the magnetic moments in solution The neutral methylpalladium chloride and the cationic methylpalladium complexes have a distorted square-planar geometry around the metal center. For the complexes of two of the ligands, an anagostic C-H¡¤¡¤¡¤Pd interaction of a ligand-proton with the palladium atom was observed in the crystal structures and in solution These interactions probably were related to hindered inversion of the six-membered metallocycle, which was observed in VT-NMR measurements. The complexes of the mesityl-substituted ligand show neither hindered inversion of the metal chelate ring nor a sign of Pd¡¤¡¤¡¤H interactions. The nickel complexes form active catalysts for the oligomerization of ethene after MAO activation. The bulky 2-tolyl and mesityl groups suppress isomerization of the growing chain, reflected in a high 1-butene selectivity. For the complex made from the ligand with the most bulky (mesityl) substituents, this selectivity was 90%. The anisyl substituents induced a different catalytic behavior of the corresponding nickel complex. Selectivity for 1-butene was lower, but the productivity was higher, with a turnover frequency of 65 ¡Á 10³ (mol C₂H₄)/(mol/Ni/h)^-1. The cationic palladium complexes showed a very low activity in ethene oligomerization. Butenes were the major product, but significant amounts of higher olefins were formed as well.

Organometallics published new progress about 23897-16-7. 23897-16-7 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Dimesitylphosphine oxide, and the molecular formula is C18H23OP, Application of Dimesitylphosphine oxide.

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

Broemmel, Kathrin published the artcileSynthesis and biological evaluation of PET tracers designed for imaging of calcium activated potassium channel 3.1 (K_Ca3.1) channels in vivo, Application of Bis(4-fluorophenyl)methane, the publication is RSC Advances (2021), 11(48), 30295-30304, database is CAplus and MEDLINE.

Expression of the Ca²⁺ activated potassium channel 3.1 (K_Ca3.1) channel (also known as the Gardos channel) is dysregulated in many tumor entities and has predictive power with respect to patient survival. Therefore, a positron emission tomog. (PET) tracer targeting this ion channel could serve as a potential diagnostic tool by imaging the K_Ca3.1 channel in vivo. It was envisaged to synthesize [¹⁸F]senicapoc ([¹⁸F]1) since senicapoc (1) shows high affinity and excellent selectivity towards the K_Ca3.1 channels. Because problems occurred during ¹⁸F-fluorination, the [¹⁸F]fluoroethoxy senicapoc derivative [18F]28 was synthesized to generate an alternative PET tracer targeting the K_Ca3.1 channel. Inhibition of the K_Ca3.1 channel by 28 was confirmed by patch clamp experiments In vitro stability in mouse and human serum was shown for 28. Furthermore, biodistribution experiments in wild type mice were performed. Since [18F]fluoride was detected in vivo after application of [¹⁸F]28, an in vitro metabolism study was conducted. A potential degradation route of fluoroethoxy derivatives in vivo was found which in general should be taken into account when designing new PET tracers for different targets with a [¹⁸F]fluoroethoxy moiety as well as when using the popular prosthetic group [¹⁸F]fluoroethyl tosylate for the alkylation of phenols.

RSC Advances published new progress about 457-68-1. 457-68-1 belongs to catalysis-chemistry, auxiliary class Fluoride,Benzene, name is Bis(4-fluorophenyl)methane, and the molecular formula is C13H10F2, Application of Bis(4-fluorophenyl)methane.

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

Wen, Ya-Ting published the artcileNi-Catalyzed Remote Radical/Cross-Electrophile Coupling Cascade for Selective C(sp³)-H Arylation, Name: 2-Methylbenzoic acid, the publication is Organic Letters (2022), 24(12), 2399-2403, database is CAplus and MEDLINE.

An innovative 1,5-HAT cascade strategy was advanced for the nickel-catalyzed distal arylation via cross-electrophile coupling. Through specific migration, the remote C(sp³)-H bond was regioselectively activated, and Ar-I as the available electrophile is used for the construction of the C(sp³)-C(sp²) bond. This method also has broad applicability for benzylic and aliphatic N-fluorocarboxamides with yields up to 80%. Furthermore, a series of control experiments demonstrated that this reaction was probably initiated by a radical process.

Organic Letters published new progress about 118-90-1. 118-90-1 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Natural product, name is 2-Methylbenzoic acid, and the molecular formula is C15H14O, Name: 2-Methylbenzoic acid.

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

Tang, Zhongping published the artcileTheoretical studies on the structure and property of alkylated diphenylamine antioxidants, Quality Control of 1821-27-8, the publication is Journal of Theoretical & Computational Chemistry (2014), 13(5), 1450035/1-1450035/17, database is CAplus.

Diarylamines (Ar₂NH) are generally used as antioxidants to inhibit or retard the auto-oxidation degradation of lubricating oil by trapping ROO¡¤ radicals. In the present study, 20 kinds of 4,4′-disubstituted diphenylamine compounds were investigated through d. functional theory (DFT) calculations The results indicate that the N-H bond dissociation enthalpy (BDE) linearly correlates its one-electron oxidation potential, the difference in Mulliken at. charge on the two atoms of N-H bond, the reaction rate constant of hydrogen transfer from Ar₂NH to peroxy radical, and the chem. hardness of the resulted Ar₂N¡¤ radical, resp. The substitution of alkyl groups (electron-donating groups) decreases the N-H BDE, one-electron oxidation potential and the reaction rate constant, while that of significant electron-withdrawing groups such as -NO₂ and -COOCH₃ increases these three parameters. The electron-donating groups such as alkyls could improve the antioxidation performance of 4,4′-disubstituted diphenylamines whereas electron-withdrawing groups have the contrary effect. In addition, the frontier MO of Ar₂NH has been also analyzed.

Journal of Theoretical & Computational Chemistry 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 C8H8N2OS, Quality Control of 1821-27-8.

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

Modrzycka, Sylwia published the artcileParallel imaging of coagulation pathway proteases activated protein C, thrombin, and factor Xa in human plasma, Synthetic Route of 71989-31-6, the publication is Chemical Science (2022), 13(23), 6813-6829, database is CAplus and MEDLINE.

Activated protein C (APC), thrombin, and factor (f) Xa are vitamin K-dependent serine proteases that are key factors in blood coagulation. Moreover, they play important roles in inflammation, apoptosis, fibrosis, angiogenesis, and viral infections. Abnormal activity of these coagulation factors has been related to multiple conditions, such as bleeding and thrombosis, Alzheimer¡äs disease, sepsis, multiple sclerosis, and COVID-19. The individual activities of APC, thrombin, and fXa in coagulation and in various diseases are difficult to establish since these proteases are related and have similar substrate preferences. Therefore, the development of selective chem. tools that enable imaging and discrimination between coagulation factors in biol. samples may provide better insight into their roles in various conditions and potentially aid in the establishment of novel diagnostic tests. In our study, we used a large collection of unnatural amino acids, and this enabled us to extensively explore the binding pockets of the enzymes¡ä active sites. Based on the specificity profiles obtained, we designed highly selective substrates, inhibitors, and fluorescent activity-based probes (ABPs) that were used for fast, direct, and simultaneous detection of APC, thrombin, and fXa in human plasma.

Chemical Science published new progress about 71989-31-6. 71989-31-6 belongs to catalysis-chemistry, auxiliary class Amino acide derivatives,pyrrolidine, name is Fmoc-Pro-OH, and the molecular formula is C20H19NO4, Synthetic Route of 71989-31-6.

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

Fordham, James M. published the artcileA “Pool and Split” Approach to the Optimization of Challenging Pd-Catalyzed C-N Cross-Coupling Reactions, Computed Properties of 1237588-12-3, the publication is Journal of Organic Chemistry (2022), 87(6), 4400-4414, database is CAplus and MEDLINE.

A screening method for the rapid identification of catalytic conditions for Pd-catalyzed C-N cross-coupling reactions was reported. The strategy evaluates mixtures of precatalysts, ligands and bases to identify productive conditions that are subsequently optimized through two deconvolution steps, which uncover the active catalyst and identify the optimal solvent and base for the catalytic system. The efficacy of this approach was demonstrated through application to a previously reported reaction, whereby both the literature conditions and addnl. solutions were retrieved. The same approach to Ni-catalyzed C-N cross-coupling was investigated in parallel but was found to be less successful due to limited activity of the evaluated reagent combinations. Finally, the utility of this method was showcased by identifying effective conditions for the Pd-catalyzed cross-coupling of complex mols., which not only revealed nonobvious solutions for the processes under evaluation, but also resulted in the discovery of new chem. reactions.

Journal of Organic Chemistry published new progress about 1237588-12-3. 1237588-12-3 belongs to catalysis-chemistry, auxiliary class Mono-phosphine Ligands, name is 4-(2-(Di(adamantan-1-yl)phosphino)phenyl)morpholine, and the molecular formula is C30H42NOP, Computed Properties of 1237588-12-3.

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