Month: December 2022

Li, Bo published the artcilePalladium-Catalyzed C(sp³)-H Nitrooxylation with tert-Butyl Nitrite and Molecular Oxygen, Category: catalysis-chemistry, the publication is Organic Letters (2020), 22(24), 9719-9723, database is CAplus and MEDLINE.

Herein, we report a Pd(II)-catalyzed nitrooxylation of unactivated Me C(sp³)-H bonds using com. available and easily manageable tert-Bu nitrite as the precursor of ONO₂ radical under aerobic conditions. Environmentally benign mol. oxygen is used to initiate the generation of active radical reactant; it is also used as the terminal oxidant. A broad range of nitrooxylated aliphatic carboxamides were prepared in moderate to good yields under mild conditions.

Organic Letters 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, Category: catalysis-chemistry.

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

Wang, Yiqing published the artcileNumerical analysis of very rich propagating spherical flames: Soot formation and its impact on the determination of laminar flame speed, HPLC of Formula: 191-07-1, the publication is Combustion and Flame (2022), 111860, database is CAplus.

Fuel-rich combustion is a promising technique to produce hydrogen by reforming hydrocarbons. Predictive modeling of the fuel reforming process needs a reliable chem. mechanism which is usually validated using laminar flame speed (LFS) data. While LFSs have been extensively employed to optimize mechanisms under fuel-lean, stoichiometric, and slightly fuel-rich conditions, it remains a formidable challenge to measure the LFSs of very rich mixtures (e.g., equivalence ratio ?¡Ý2) due to significant soot formation in such conditions, which leads to the LFS data under fuel-rich conditions being rather scarce. To overcome the challenge, a clear understanding of soot formation and its impact on LFS measurements is required. In this work, a series of one-dimensional outwardly propagating spherical flames (OPFs) with and without considering soot formation are simulated for rich ethylene/air mixtures (2.0¡Ü?¡Ü3.5), in order to understand soot dynamics and morphol. in the OPFs and to quantify the effects of soot formation on the determination of LFS using the OPF method under fuel-rich conditions. To this end, a detailed chem. accounting for major pathways of PAH formation up to A7 (coronene, C₂₄H₁₂) is employed and coupled with a state-of-the-art soot model considering nucleation, condensation, coagulation, surface growth, oxidation, and fragmentation. It is found that soot dynamics and morphol. are very sensitive to the change in equivalence ratio and flame radius. Specifically, surface growth and oxidation play a dominant role in soot formation/evolution and can balance each other at ? = 2.0, resulting in limited soot formation. However, the PAH-based condensation can dominate over other processes at ?¡Ý2.5 and hence a large amount of soot is observed Moreover, the maximum value of primary particle diameters would tend to a constant as the flame radius increases. The results also show that the ratio between total soot mass and the mass of burned gas, msoot/mburned, follows an exponential law given by msoot/mburned = 100.47?-3.76, implying that soot formation can be exponentially enhanced by increasing equivalence ratio. Furthermore, it is found that under very rich conditions, the presence of soot has a significant impact on the determination of LFS, which leads to the measured LFS at ? = 3.5 being 22% lower than 1D planar adiabatic flame speed. This is mainly attributed to the thermal and flow effects of soot radiation, i.e., the reduction of flame temperature and neg. flow speed of the burned gas. The above findings suggest that the impact of soot radiation should be carefully treated when determining the LFSs of rich premixed mixtures at ?¡Ý2.0.

Combustion and Flame published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C18H35NO, HPLC of Formula: 191-07-1.

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

Deng, Zhixin published the artcileLigand-enabled palladium-catalyzed hydroesterification of vinyl arenes with high linear selectivity to access 3-arylpropanoate esters, Name: 2-Methylbenzoic acid, the publication is Chemical Communications (Cambridge, United Kingdom) (2022), 58(24), 3921-3924, database is CAplus and MEDLINE.

Palladium-catalyzed linear-selective hydroesterification of vinyl arenes with alcs. enabled by diphosphine ligands derived from bis[2-(diphenylphosphino)ethyl]amides has been developed. A variety of 3-arylpropanoate esters were obtained in high yields and regioselectivity. The robustness of this methodol. was further demonstrated by the efficient gram-scale synthesis of the Et 3-phenylpropanoate as a precursor to hydrocinnamic acid.

Chemical Communications (Cambridge, United Kingdom) 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 C8H8O2, Name: 2-Methylbenzoic acid.

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

Sun, Hao published the artcileApproach to Vicinal t-Boc-amino Dibromides via Catalytic Aminobromination of Nitrostyrenes without Using Chromatography and Recrystallization, Application In Synthesis of 4230-93-7, the publication is Journal of Organic Chemistry (2013), 78(3), 1171-1175, database is CAplus and MEDLINE.

In the presence of tripotassium phosphate trihydrate, tert-Bu N,N-dibromocarbamate (prepared from tert-Bu carbamate) added regioselectively to ¦Â-nitrostyrenes RCH:CHNO₂ [R = Ph, 4-ClC₆H₄, 4-MeOC₆H₄, 2-ClC₆H₄, 4-MeC₆H₄, 4-F₃CC₆H₄, 4-NCC₆H₄, 2-naphthyl, 1-naphthyl, 2-PhCH₂OC₆H₄, 2,6-Cl₂C₆H₃, 3,4-Cl₂C₆H₃, 4-FC₆H₄, 4-BrC₆H₄, 3-FC₆H₄, 3-Br-4-MeOC₆H₃, 2-MeOC₆H₄, 3,4-(MeO)₂C₆H₃, 4-Me₃CC₆H₄] in 1,2-dichloroethane to give tert-Bu ¦Á-(dibromonitromethyl)benzylcarbamates RCH(NHBoc)C(NO₂)Br₂ [R = Ph, 4-ClC₆H₄, 4-MeOC₆H₄, 2-ClC₆H₄, 4-MeC₆H₄, 4-F₃CC₆H₄, 4-NCC₆H₄, 2-naphthyl, 1-naphthyl, 2-PhCH₂OC₆H₄, 2,6-Cl₂C₆H₃, 3,4-Cl₂C₆H₃, 4-FC₆H₄, 4-BrC₆H₄, 3-FC₆H₄, 3-Br-4-MeOC₆H₃, 2-MeOC₆H₄, 3,4-(MeO)₂C₆H₃, 4-Me₃CC₆H₄] in 82-99% yields. The solubility of the products allowed them to be isolated in pure form by extraction with hexanes rather than requiring chromatog. or recrystallization for purification

Journal of Organic Chemistry published new progress about 4230-93-7. 4230-93-7 belongs to catalysis-chemistry, auxiliary class Alkenyl,Nitro Compound,Benzene,Ether, name is 1,2-Dimethoxy-4-(2-nitrovinyl)benzene, and the molecular formula is C15H14O, Application In Synthesis of 4230-93-7.

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

Choi, Jin published the artcileEffects of dietary docosahexaenoic acid enrichment in Artemia feed on the growth, survival, and fatty acid composition of Pacific cod (Gadus macrocephalus) larvae, Recommanded Product: Docosahexaenoic Acid, the publication is Aquaculture Research (2022), 53(12), 4353-4362, database is CAplus.

Optimal larviculture techniques have yet to be established for Pacific cod (Gadus macrocephalus), particularly in relation to the nutritional quality of live prey. Elevated mortality during early life stages is a major concern during the production of Pacific cod larvae; this seems to be related to, among other things, nutritional deficiency during the early feeding stage, particularly the quantities and proportions of highly unsaturated fatty acids in live food. With the aim of improving the growth and survival of larval Pacific cod while also determining the optimum level of dietary docosahexaenoic acid (DHA), we investigated the effects of four levels of dietary DHA (0%, 3%, 6%, and 9% of total fatty acids [TFAs]) on the growth, survival, and tissue fatty composition of larvae. The actual DHA concentrations of the diets were 0.22%, 3.09%, 5.88%, and 9.28% of TFAs for D1, D2, D3, and D4 diets resp. From 43 to 64 days post hatch, larvae were fed the exptl. diets. Larvae fed D3 diet had the highest survival rates, total length, and total weight at the end of the feeding trial. The fatty acid composition of the whole larval body reflected the corresponding dietary composition Overall, these results suggest that a DHA level of 4.85%-8.50% of TFAs is optimal in the diet of larval Pacific cod during Artemia feeding.

Aquaculture Research 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, Recommanded Product: Docosahexaenoic Acid.

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

Mathias, A. published the artcileNitrogen-14 chemical shifts in substituted anilines, Formula: C12H9N3O4, the publication is Journal of the Chemical Society [Section] B: Physical Organic (1971), 397-9, database is CAplus.

Amino-14N chem. shifts of the anilines XC6H4NH2 (X = H; p-NO2, p-Ac, p-AcO, p-Br, p-Cl, p-Me, p-NH2, m-NO2, m-Ac, m-CF3, m-CO2Me, m-Me) and PhNHX (X = Me, Ph, m-MeOC6H4, p-MeOC6H4) and (p-O2NC6H4)2NH in Me2CO were determined by the heteronuclear double resonance method. The shifts correlated linearly with Hammett ¦Ò values of the ring substituents and related directly to electron ds. at the N nucleus. The 14N and 15N chem. shifts (Bramwell, M. R., Radall, E. W., 1969) of XC6H4NH2 (X = p-Me, p-Br, p-NO2, H) were identical.

Journal of the Chemical Society [Section] B: Physical Organic 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, Formula: C12H9N3O4.

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

Tang, Zeyuan published the artcileDimerization of dehydrogenated polycyclic aromatic hydrocarbons on graphene, Quality Control of 191-07-1, the publication is Journal of Chemical Physics (2022), 156(13), 134703, database is CAplus and MEDLINE.

Dimerization of polycyclic aromatic hydrocarbons (PAHs) is an important, yet poorly understood, step in the on-surface synthesis of graphene (nanoribbon), soot formation, and growth of carbonaceous dust grains in the interstellar medium (ISM). The on-surface synthesis of graphene and the growth of carbonaceous dust grains in the ISM require the chem. dimerization in which chem. bonds are formed between PAH monomers. An accurate and cheap method of exploring structure rearrangements is needed to reveal the mechanism of chem. dimerization on surfaces. This work has investigated the chem. dimerization of two dehydrogenated PAHs (coronene and pentacene) on graphene via an evolutionary algorithm augmented by machine learning surrogate potentials and a set of customized structure operators. Different dimer structures on surfaces have been successfully located by our structure search methods. Their binding energies are within the exptl. errors of temperature programmed desorption measurements. The mechanism of coronene dimer formation on graphene is further studied and discussed. (c) 2022 American Institute of Physics.

Journal of Chemical Physics published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C12H10F2Si, Quality Control of 191-07-1.

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

Otsuka, Masami published the artcileSynthesis, structure of copper(II) complexes of S-containing pentadentate ligands, Application In Synthesis of 6950-53-4, the publication is Journal of Organometallic Chemistry (2000), 611(1-2), 577-585, database is CAplus.

Novel ligands containing a pyridine and methylsulfanyl groups, 2,6-bis[(2-methylsulfanylethylamino)methyl]pyridine (4) and 2,6-bis[(2-methylsulfanylethylamino)methyl]-4-dimethylaminopyridine (7) were prepared and the properties of their copper complexes were studied. Potentiometric titration, absorption and ESR spectral measurements, and x-ray crystallog. of copper complexes of 4 and 7 were carried out. The x-ray structures of [Cu(4)](ClO₄)₂ and [Cu(7)](ClO₄)₂ revealed an intermediate geometry between the regular trigonal bipyramid with two secondary amines being axial and the regular square pyramid with one of the thioethers being in the apical position.

Journal of Organometallic Chemistry published new progress about 6950-53-4. 6950-53-4 belongs to catalysis-chemistry, auxiliary class Salt,sulfides,Amine,Aliphatic hydrocarbon chain, name is 2-(Methylthio)ethanamine hydrochloride, and the molecular formula is C3H10ClNS, Application In Synthesis of 6950-53-4.

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

Gaboriaud, R. published the artcileDetermination of the pKa of very weak acids by extrapolation methods in water-dimethyl sulfoxide media, SDS of cas: 1821-27-8, the publication is Bulletin de la Societe Chimique de France (1976), 1093-8, database is CAplus.

The empirical function pK(AH)-pK(reference) = ¦Á + ¦Âg(S) for solvent blends introduced earlier (1973), was applied to indole, Ph2NH, PhNH2, and aminopyridine derivatives dissolved in aqueous DMSO. The linear correlation readily permits an extrapolation to calculate pK values at 20¡ã for solutions in pure H2O (g(S)). The pK values correspond well with values determined in concentrated LiOH, NaOH, and KOH solutions

Bulletin de la Societe Chimique de France 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

Appleton, T. G. published the artcileComplexes with six-membered chelate rings. II. Proton magnetic resonance study of trimethylenediamine, some methyl-substituted derivatives, and their complexes with platinum(II) and palladium(II), Application of Propane-1,3-diamine dihydrochloride, the publication is Inorganic Chemistry (1970), 9(8), 1807-14, database is CAplus.

PMR spectra of compounds (diamine)(HCl)2, M(diamine)22+, and M(diamine)(NH3)22+ are reported, where M = Pt(II), Pd(II); diamine = trimethylenediamine, 2-methylpropane-1,3-diamine, pentane-2,4-diamine, neopentanediamine, ethylenediamine, meso-butane-2,3-diamine. These spectra are discussed in terms of the conformational behavior of the chelate rings. An unusual Pt-H coupling over 4 saturated bonds is observed in some complexes.

Inorganic Chemistry 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 C3H12Cl2N2, Application of Propane-1,3-diamine dihydrochloride.

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