Catalysis-chemistry

Deng, Chen-Qiang published the artcileNi-Catalyzed Asymmetric Hydrogenation of Aromatic Ketoacids for the Synthesis of Chiral Lactones, Related Products of catalysis-chemistry, the publication is Organic Letters (2022), 24(13), 2494-2498, database is CAplus and MEDLINE.

A highly efficient Ni-catalyzed asym. hydrogenation of aromatic ¦Ã- and ¦Ä-ketoacids has been developed, affording a series of ¦Ã- and ¦Ä-aryl lactones in high yields and excellent enantioselectivities (¡Ü98% ee). The hydrogenation could occur smoothly on a gram scale with 0.05 mol % catalyst loading (S/C = 2000). This protocol provides an efficient and practical approach for accessing chiral lactones with important potential applications in organic synthesis and the pharmaceutical industry.

Organic Letters published new progress about 2051-95-8. 2051-95-8 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ketone, name is 3-Benzoylpropionicacid, and the molecular formula is C10H10O3, Related Products of catalysis-chemistry.

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

Potapov, V. M. published the artcileEffect of the relative position of chromophores on the chiroptical properties of aralkanoic acids with an asymmetrical atom in the ¦Á-position to the carboxylic group, Recommanded Product: 2-Methyl-4-phenylbutanoic acid, the publication is Zhurnal Organicheskoi Khimii (1981), 17(11), 2329-33, database is CAplus.

The CD spectra of (R)-(-)-Ph(CH₂)_nCHMeCO₂H (n = 0, 1, 2) were recorded. As n increased, the Cotton effect curve at ?220 nm exhibited a hypochromic shift and a decrease in intensity.

Zhurnal Organicheskoi Khimii published new progress about 1949-41-3. 1949-41-3 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene, name is 2-Methyl-4-phenylbutanoic acid, and the molecular formula is C11H14O2, Recommanded Product: 2-Methyl-4-phenylbutanoic acid.

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

Roos, Casey B. published the artcileEnantioselective Hydroamination of Alkenes with Sulfonamides Enabled by Proton-Coupled Electron Transfer, Recommanded Product: 2,4,6-Triisopropylbenzenethiol, the publication is Journal of the American Chemical Society (2020), 142(13), 5974-5979, database is CAplus and MEDLINE.

An enantioselective, radical-based method for the intramol. hydroamination of alkenes with sulfonamides to afford pyrrolidines I [R¹ = Ph, 2-thienyl, 2,4,6-tri-MeC₆H₂, etc.; R² = H, Me; R³ = Me, t-Bu, CH₂CH₂CH=CMe₂; R²R³ = (CH₂)₂, (CH₂)₅, CH₂CH₂NBocCH₂CH₂] was reported. These reactions were proposed to proceed via N-centered radicals formed by proton-coupled electron transfer (PCET) activation of sulfonamide N-H bonds. Noncovalent interactions between the neutral sulfonamidyl radical and a chiral phosphoric acid generated in the PCET event were hypothesized to serve as the basis for asym. induction in a subsequent C-N bond forming step, achieving selectivities of up to 98:2 er. These results offer further supported for the ability of noncovalent interactions to enforce stereoselectivity in reactions of transient and highly reactive open-shell intermediates.

Journal of the American Chemical Society published new progress about 22693-41-0. 22693-41-0 belongs to catalysis-chemistry, auxiliary class Other Functionalization Reagent, name is 2,4,6-Triisopropylbenzenethiol, and the molecular formula is C15H24S, Recommanded Product: 2,4,6-Triisopropylbenzenethiol.

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

Botta, Bruno published the artcileSynthesis of C-Alkylcalix[4]arenes. 4. Design, Synthesis, and Computational Studies of Novel Chiral Amido[4]resorcinarenes, Safety of (E)-3-(2,4-Dimethoxyphenyl)acrylic acid, the publication is Journal of Organic Chemistry (1997), 62(4), 932-938, database is CAplus.

In extending our studies involving BF₃¡¤Et₂O-catalyzed reaction of cinnamic acid analogs, we have shown that amido derivatives also can afford [4]resorcinarene octamethyl ethers. Subsequently, chiral monomeric amides, derived from the mixed anhydride of cinnamic acid and L– or D-valine, upon treatment with BF₃¡¤Et₂O, yielded for the first time chiral amido[4]resorcinarenes in enantiomerically pure forms. Four stereoisomers were isolated, and three of them were assigned the flattened-cone, chair, and 1,2-alternate conformations. The major product was assigned a novel chairlike structure, namely, flattened partial cone 1. The flattened-cone stereoisomer, which was indicated by mol. modeling studies to be the most stable, became the major product under more drastic exptl. conditions. Chromatog. studies on chiral phases revealed that the above tetramers could be used for the enantiodiscrimination of racemic mols.

Journal of Organic Chemistry 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

Cauquis, G. published the artcileElectrochemical properties of diphenylamines and of their oxidation products in organic media. III. p,p’-Disubstituted diphenylamines and production of their primary cation radicals, SDS of cas: 1821-27-8, the publication is Electrochimica Acta (1976), 21(8), 557-65, database is CAplus.

The electrochem. oxidation of 2,2′,4,4′-tetramethoxydiphenylamine [7093-78-9] on bright Pt in neutral media, studied by cyclic voltammetry, ESR, and uv spectroscopy, gives 3 waves. The 1st wave corresponds to formation of the stable radical cation [54323-77-2], the 2nd wave to further oxidation to the nitrenium ion [61236-17-7] via the dication, and the final step results in formation of the aryl p-benzoquinoneimine. In 2,6-lutidine the nitrenium ion is observed before conversion to a heptamethoxydihydrophenazine, the exact formula of which is unknown. Oxidation of p,p’-disubstituted diphenylamines, e.g. p,p’-diaminodiphenylamine [537-65-5] in basic media gives the corresponding radical cations. In strong base, these lead to tetraarylhydrazines but in pyridine-like bases and, in some cases, H2O diaryldihydrophenazines are formed.

Electrochimica Acta 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, SDS of cas: 1821-27-8.

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

Vermeulen, Nicolaas A. published the artcileSynthesis of Complex Allylic Esters via C-H Oxidation vs C-C Bond Formation, Product Details of C11H12O4, the publication is Journal of the American Chemical Society (2010), 132(32), 11323-11328, database is CAplus and MEDLINE.

A highly general, predictably selective C-H oxidation method for the direct, catalytic synthesis of complex allylic esters is introduced. This Pd(II)/sulfoxide-catalyzed method allows a wide range of complex aryl and alkyl carboxylic acids R¹CO₂H [R¹ = Me, Ph, (E)-2,4-(MeO)₂C₆H₃CH:CH, 3,4-F₂C₆H₃CH₂, BocNHCH₂CH₂, etc.] to couple directly with terminal olefins R²CH₂CH:CH₂ (R² = Ph, benzodioxolan-5-yl, t-BuSiMe₂CH₂CH₂, etc.) to furnish (E)-allylic esters R²CH:CHCH₂OCOR¹ in synthetically useful yields and selectivities (16 examples, E/Z ¡Ý 10:1) and without the use of stoichiometric coupling reagents or unstable intermediates. Strategic advantages of constructing allylic esters via C-H oxidation vs C-C bond-forming methods are evaluated and discussed in four “case studies”.

Journal of the American 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 C15H21BO2, Product Details of C11H12O4.

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

De Bruycker, Kevin published the artcileCovalent Fluorination Strategies for the Surface Modification of Polydienes, Synthetic Route of 30670-30-5, the publication is Macromolecular Rapid Communications (2017), 38(11), n/a, database is CAplus and MEDLINE.

Nonreactive additives are widely applied to enhance polymer properties but can leach out of the material over time. In this work, two essentially different fluorinated additives bearing a triazolinedione moiety are synthesized and grafted on several polydiene backbones (acrylonitrile-butadiene-styrene, styrene-butadiene, and styrene-isoprene-styrene (SIS) copolymers), either by dip-coating or by reaction in solution The resulting polymers are analyzed by contact angle goniometry, size exclusion chromatog., and NMR, IR, and XPS. Independent of the modification procedure, the fluorophilic perfluoroalkyl additive is found at the material surface, thereby yielding a more hydrophobic surface. For SIS thermoplastic elastomers, for example, contact angles up to 125¡ã can be obtained.

Macromolecular Rapid Communications published new progress about 30670-30-5. 30670-30-5 belongs to catalysis-chemistry, auxiliary class Polyfluoroalkanes, name is 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodecan-1-amine, and the molecular formula is C10H6F17N, Synthetic Route of 30670-30-5.

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

Hevesi, L. published the artcilePeculiarities in the cleavage by methyllithium of unsymmetrical disilanes, Application of Trimethyl(perfluorophenyl)silane, the publication is Tetrahedron Letters (1994), 35(43), 8031-2, database is CAplus.

The title reactions did not produce the more stable silyl anions from the disilanes studied. These reactions either occurred by attack at the more electrophilic Si atom, or led to unexpected products. Three different reaction pathways were observed, depending on the substituents. Thus, treating Me₃SiSiMe₂C₆H_nX_5-n (X = H; X = 4-Cl, n = 4; X = 3-CF₃, 4-Cl, n = 3 1a–c) with MeLi in HMPA gave predominantly Me₃SiC₆H_nX_5-n. Similar reaction of 1d (X = 3,5-Cl₂, n = 3) gave almost quant. m-Cl₂C₆H₄, whereas 1e (X = F₅, n = 0) gave C₆HF₅ and polymeric -(Me₂Si)-_n.

Tetrahedron Letters 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

Bausinger, Tobias published the artcileDetermination of nitrodiphenylamines and related compounds in the leachate water of a military contaminated site, Product Details of C12H9N3O4, the publication is Umweltwissenschaften und Schadstoff-Forschung (2005), 17(1), 7-12, database is CAplus.

Nitrodiphenylamines can be found at abandoned military sites where the explosive 2,2′,4,4′,6,6′-hexanitrodiphenylamine (hexyl) or diphenylamine as a stabilizer of smokeless powder was handled. Aim of the present study is the development of HPLC methods for the anal. of contaminants which can be expected in particular under aerobic conditions at premises which are contaminated by nitrodiphenylamines and related compounds A list of 13 compounds which can be expected at these explosives factories was deduced from literature studies. HPLC methods were developed for the analytes. Water samples from the unsaturated zone of a former hexyl-producing factory were collected by suction cups and the material was analyzed according to these procedures to demonstrate the practicability of the new methods and to verify the existence of the postulated compounds in the environment of the former nitration plant. The new HPLC methods are suitable for the exploration of sites contaminated by nitrodiphenylamines. Beside some hexyl its intermediates 1-chloro-2,4-dinitrobenzene, 2,4-dinitrodiphenylamine and 2,2′,4,4′-tetranitrodiphenylamine were identified in the leachate water. It is advisable to include at least these 4 compounds in the examination of former hexyl-producing plants. Several unknown peaks were observed in the HPLC-chromatogram. It is recommendable to perform further investigations of the unidentified compounds to compile a final list of analytes for military sites polluted by nitrodiphenylamines.

Umweltwissenschaften und Schadstoff-Forschung 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, Product Details of C12H9N3O4.

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

Rabinovitch, Michel published the artcileDestruction of Leishmania mexicana amazonensis amastigotes within macrophages in culture by phenazine methosulfate and other electron carriers, Synthetic Route of 10510-54-0, the publication is Journal of Experimental Medicine (1982), 155(2), 415-31, database is CAplus and MEDLINE.

Exposure of macrophages infected with L. mexicana?amazonensis to phenazine?methosulfate (PMS) [299-11-6] resulted in rapid damage and disappearance of the intracellular amastigotes without obvious ill effects to the host cells. The reduction of the percent infection was related to the concentration of PMS and to the duration of the pulse. Most Leishmania disappeared within 2 h of a 2-h pulse with 10 ¦ÌM of the drug. In contrast, pretreatment of the macrophages with PMS followed by removal of the drug before infection did not result in disappearance of the parasites. The pH of the PMS medium markedly influenced the disappearance of Leishmania: maximum effect was observed at pH 8.0, while the effect was negligible at pH 6.3. The pH effect may be related to pseudobase formation by the PMS cation. Dose-response curves for PMS were similar for resident, elicited, or activated macrophages. Observations by time-lapse cinemicrog. documented the explosion-like fragmentation of the amastigotes within 1-2 h of exposure of infected macrophages to the drug. Parasite-derived granules and vacuoles were seen to scatter within the parasitophorous vacuoles. This early damage to the parasites was confirmed by transmission electron microscopic observations. Infected macrophages incubated with PMS displayed detectable vacuolar fluorescence, indicating that PMS or a metabolite of PMS had access to the vacuoles. A series of other electron carriers, including phenylmethanes, phenazines, oxazines, a xanthene, and a naphthoquinone, given continuously for 18 h, also induced the disappearance of the Leishmania. The most potent was crystal?violet??[548-62-9], active at 70 nM. The presence of apolar substituents enhanced activity and this is probably related to increased permeation of the dyes. Finally, PMS, as well as other electron carriers examined, also reduced the growth of Leishmania promastigotes in culture. The results are compatible with a direct effect of the drugs on the intracellular amastigotes, involving only a permissive participation of the macrophages. The diverse agents may destroy the amastigotes by redox-cycling generation of active O metabolites at or near the parasites. Alternatively, the effect of the drugs could be mediated by toxic free radical reduction species of the drugs or by interference with electron flow or with the intermediary metabolism of Leishmania.

Journal of Experimental Medicine published new progress about 10510-54-0. 10510-54-0 belongs to catalysis-chemistry, auxiliary class Other Aromatic Heterocyclic,Salt,Amine,Inhibitor,Inhibitor, name is 5,9-Diaminobenzo[a]phenoxazin-7-ium acetate, and the molecular formula is C18H15N3O3, Synthetic Route of 10510-54-0.

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