Catalysis-chemistry

Priyadarshini, S. published the artcileCopper catalyzed cross-coupling reactions of carboxylic acids: an expedient route to amides, 5-substituted ¦Ã-lactams and ¦Á-acyloxy esters, Safety of (E)-3-(2,4-Dimethoxyphenyl)acrylic acid, the publication is RSC Advances (2013), 3(40), 18283-18287, database is CAplus.

A convenient and recyclable catalytic protocol for the synthesis of N,N-di-Me substituted amides, 5-substituted ¦Ã-lactams, and ¦Á-acyloxy ethers from carboxylic acids using CuO nanoparticles and TBHP is described.

RSC Advances 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

LoCoco, Matthew D. published the artcileChelate-Controlled Synthesis of rac- and meso-Me₂Si(3-^tBu-C₅H₃)₂ZrCl₂, Application In Synthesis of 10517-44-9, the publication is Organometallics (2003), 22(26), 5498-5503, database is CAplus.

The reaction of the chelated bis-amide complex Zr{PhN(CH₂)₃NPh}Cl₂(THF)₂ (2) with Li₂[Me₂Si(3-^tBu-C₅H₃)₂] yields meso-Me₂Si(3-^tBu-C₅H₃)₂Zr{PhN(CH₂)₃NPh} (meso-3) in >98% yield. In contrast, the reaction of Zr{Me₃SiN(CH₂)₃NSiMe₃}Cl₂(THF)₂ (4) or the related mono-THF adduct Zr{Me₃SiN(CH₂)₃NSiMe₃}Cl₂(THF) (5) with Li₂[Me₂Si(3-^tBu-C₅H₃)₂] yields rac-Me₂Si(3-^tBu-C₅H₃)₂Zr{Me₃SiN(CH₂)₃NSiMe₃} (rac-6) in quant. NMR yield and 89% isolated yield. X-ray crystallog. analyses show that the Zr{RN(CH₂)₃NR} chelate ring in rac-6 has a pronounced twist conformation, while that in meso-3 has a flatter, envelope conformation. It is proposed that the conformations of the Zr{RN(CH₂)₃NR} chelate rings in the stereodetermining transition states for addition of the second Cp^– ring in these reactions are similar to those in the metallocene products and control the diastereoselectivity. Meso-3 and rac-6 are converted to meso-Me₂Si(3-^tBu-C₅H₃)₂ZrCl₂ (meso-1) and rac-1, resp., by reaction with HCl in Et₂O.

Organometallics 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 In Synthesis of 10517-44-9.

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

Schirmer, Marie-Luis published the artcileOrganocatalyzed Reduction of Tertiary Phosphine Oxides, Category: catalysis-chemistry, the publication is Advanced Synthesis & Catalysis (2016), 358(1), 26-29, database is CAplus.

A novel selective catalytic reduction method of tertiary phosphine oxides to the corresponding phosphines has been developed. Notably, the reaction proceeds smoothly with low catalyst loadings of 1-5 mol% even at low temperature (70¡ã). Under the optimized conditions various phosphine oxides could be selectively reduced and the desired phosphines were usually obtained in excellent yields above 90%. Furthermore, authors have developed a one-pot reaction sequence for the preparation of valuable phosphine¡¤borane adducts. Simple addition of BH₃¡¤THF subsequent to the reduction step gave the desired adducts in yields up to 99%.

Advanced Synthesis & Catalysis published new progress about 4141-48-4. 4141-48-4 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Allyldiphenylphosphine oxide, and the molecular formula is C15H15OP, Category: catalysis-chemistry.

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

Taouss, Christina published the artcileStructure of the adducts methylthiourea: 1,4-dioxane (2:1) and 1,1-dimethylthiourea: morpholine (1:1), HPLC of Formula: 6972-05-0, the publication is Zeitschrift fuer Naturforschung, B: A Journal of Chemical Sciences (2016), 71(8), 905-907, database is CAplus.

The adducts methylthiourea:1,4-dioxane (2:1) (1) and 1,1-dimethylthiourea:morpholine (1:1) (2) were prepared and their crystal structures determined In 1, hydrogen bonding involving the methylthiourea mols. leads to the formation of R²₂(8) rings and thence to mol. ribbons parallel to [110]. The dioxane mols. accept hydrogen bonds from the remaining NH groups, and their inversion symmetry means that they connect adjacent methylthiourea ribbons, forming a layer structure parallel to (11?1). In the packing of 2, dimethylthiourea dimers cannot link to each other because of the blocking effect of their Me groups, but instead are linked indirectly via morpholine mols., the NH groups of which are simultaneously hydrogen bond acceptors from the remaining NH function of dimethylthiourea and donors towards the sulfur atom of a neighboring dimer. The overall effect is to form broad ribbons parallel to the a axis, with the morpholine mols. occupying the peripheral positions. The morpholine oxygen atom of 2 is not involved in classical hydrogen bonds.

Zeitschrift fuer Naturforschung, B: A Journal of Chemical Sciences published new progress about 6972-05-0. 6972-05-0 belongs to catalysis-chemistry, auxiliary class Thiourea,Amine,Aliphatic hydrocarbon chain,Amide, name is 1,1-Dimethylthiourea, and the molecular formula is C9H6N2O2, HPLC of Formula: 6972-05-0.

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

Basinger, Mark A. published the artcileRelative efficacy of chelating agents as antidotes for acute nickel(II) acetate intoxication, HPLC of Formula: 38260-01-4, the publication is Research Communications in Chemical Pathology and Pharmacology (1980), 30(1), 133-41, database is CAplus and MEDLINE.

The relative efficacy of 14 chelating agents in alleviating acute Ni(OAc)₂ [373-02-4] (i.p.) intoxication was determined The LD₅₀ for i.p. Ni(OAc)₂ in mice was 45.7 mg/kg with a 95% confidence limit of 39.2-53.3 mg/kg. With 62 mg Ni(OAc)₂/kg (i.p.) (i.e. ¡ÝLD₉₀), the most effective antidotes were D-penicillamine [52-67-5] and Na₂CaEDTA [62-33-9]. The acetylation of the NH₂ group in penicillamine to give N-acetyl-D,L-penicillamine [59-53-0] effectively destroys the antidotal action, as would be expected if coordination to the N were essential to the process.

Research Communications in Chemical Pathology and Pharmacology published new progress about 38260-01-4. 38260-01-4 belongs to catalysis-chemistry, auxiliary class Chelating Agents, name is N1,N1′-(Ethane-1,2-diyl)bis(ethane-1,2-diamine) dihydrochloride, and the molecular formula is C6H20Cl2N4, HPLC of Formula: 38260-01-4.

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

Exner, O. published the artcileQuantitative evaluation of the inductive effect, Application In Synthesis of 31719-76-3, the publication is Collection of Czechoslovak Chemical Communications (1962), 02296-306, database is CAplus.

The relative pK’ values obtained by measuring the dissociation constants of p-toluic acids, substituted in the Me group, in 50% (by volume) aqueous EtOH (I) and 80% (by weight) Methyl Cellosolve (II), are considered as a measure of the inductive effect of the substituents. From the results it follows that the transmission of the inductive effect takes place predominantly along the ¦Ä-bonds (and not space). Refluxing p-ClCH₂C₆H₄CN (IIa) with azeotropic HBr 12 hrs. gave 62% p-BrCH₂C₆H₄CO₂H, m. 229¡ã (EtOH), also formed in 90% yield by refluxing p-HOCH₂C₆H₄CO₂Me with the same reagent. p-ClCH₂C₆H₄CO₂H (III) (1.71 g.) and 4 g. NaI refluxed 1 hr. in 30 ml. Me₂CO, the solution evaporated to dryness in vacuo, the inorganic salts washed out with H₂O, and the product washed with a dilute solution of Na₂S₂O₃ gave 66% p-ICH₂C₆H₄CO₂H, m. 235¡ã (EtOH). Refluxing 1.71 g. III with 0.46 g. Na in 30 ml. absolute MeOH 3 hrs., evaporating the MeOH in vacuo, and precipitating by HCl gave 70% p-MeOCH₂C₆H₄CO₂H, m. 108¡ã (CHCl₃, petr. ether). Similar procedure with 1.71 g. III, 0.94 g. PhOH, and 0.46 g. Na in 30 ml. MeOH gave 55% p-PhOCH₂C₆H₄CO₂H, m. 216¡ã (dilute EtOH). Adding 0.8 ml. AcCl to 1.52 g. p-HOCH₂C₆H₄C0₂H in 5 ml. C₅H₅N, cooling the mixture after 15 min., and pouring into dilute HCl gave 88% p-AcOCH₂C₆H₄CO₂H, m. 128¡ã (C₆H₆). p-PhCH₂C₆H₄CO₂H, prepared from p-BrCH₂C₆H₄CN (IV) and C₆H₆ in a 68% overall yield, m. 160¡ã (dilute EtOH). Partial hydrolysis of p-NCCH₂C₆H₄CO₂H afforded 51% p-H₂NCOCH₂C₆H₄CO₂H, m. 274¡ã (EtOH). Refluxing 1.71 g. III with 1 g. NaSCN in 30 ml. EtOH 3 hrs., evaporating the solution to dryness in vacuo, eluting the salts with H₂O, and repptg. the crude product from 10% aqueous KOH gave 80% p-NCSCH₂C₆H₄CO₂H, m. 172¡ã (EtOAc). Refluxing 1.61 g. p-BrCH₂C₆H₄CO₂H with 2.2 g. PhSO₂Na in 25 ml. EtOH 8 hrs. yielded 95% p-PhSO₂CH₂C₆H₄CO₂H, m. 306¡ã (decomposition) (EtOH). Adding 4.9 g. IV to a mixture of 8.2 g. Me₂NH.HCl and 3.5 g. NaOH in 10 ml. H₂O and 25 ml. EtOH, allowing the mixture to stand overnight, refluxing 30 min., evaporating the EtOH in vacuo, dissolving the residue in H₂O, extracting the solution with three 15-ml. portions CHCl₃, evaporating the extract, refluxing the residue 3 hrs. with a solution of 3 g. NaOH in 20 ml. 50% EtOH, acidifying the reaction mixture with HCl, evaporating to dryness in vacuo, and extracting the residue with boiling EtOH gave 56% p-Me₂NCH₂C₆H₄CO₂H.HCl, m. 256¡ã (EtOH). Allowing a mixture of 3.03 g. IIa and 2.8 g. (CH₂)₆N₄ in 50 ml. CHCl₃ to stand 2 days at room temperature, concentrating the solution to 10 ml. in vacuo, filtering off 4.11 g. of a salt, dissolving it in 20 ml. 1:2 HCl and EtOH, distg, to dryness in vacuo, and extracting the residue with Me₂CO gave 52% p-H₂NCH₂C₆H₄CN.HCl, m. 269¡ã (EtOH). Hydrolysis by refluxing 16 hrs. with concentrated HCl, followed by acetylation with AcCl in pyridine, gave 43% p-Ac-NHCH₂C₆H₄CO₂H, m. 201¡ã (EtOH). The measurements of the apparent dissociation constants were carried out using an electronic pH meter with a vibrating condenser and a cell having a glass electrode and calomel reference electrode. The substances in concentrations of the order of 10^-3M were titrated with aqueous Me₄OH. The apparent dissociation constants (pK’) in solvents I and II for the appropriate substituents in ¦Á-position of p-MeC₆H₄CO₂H are for: H, 5.78, 6.82; Cl, 5.36, 6.45; Br, 5.36, 6.36; iodine, 5.41, 6.41; Ph, 5.70, 6.73; CN, 5.28, 6.32; CONH₂, 5.44, 6.69; OH, 5.56, 6.70; OMe, 5.50, 6.58; OPh, 5.43, 6.56; OAc, 5.46, 6.50; NHAc, 5.61, 6.68; NMe₂.HCl, 4.67, –; SCN, 5.33, 6.46; and PhSO₂, –, 6.36.

Collection of Czechoslovak Chemical Communications published new progress about 31719-76-3. 31719-76-3 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ether, name is 4-(Phenoxymethyl)benzoic acid, and the molecular formula is C14H12O3, Application In Synthesis of 31719-76-3.

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

Graves, Brian M. published the artcileComprehensive characterization of mainstream marijuana and tobacco smoke, Formula: C14H14, the publication is Scientific Reports (2020), 10(1), 7160, database is CAplus and MEDLINE.

Recent increases in marijuana use and legalization without adequate knowledge of the risks necessitate the characterization of the billions of nanoparticles contained in each puff of smoke. Tobacco smoke offers a benchmark given that it has been extensively studied. Tobacco and marijuana smoke particles are quant. similar in volatility, shape, d. and number concentration, albeit with differences in size, total mass and chem. composition Particles from marijuana smoke are on average 29% larger in mobility diameter than particles from tobacco smoke and contain 3.4 times more total mass. New measurements of semivolatile fractions determined that >97% of the mass and volume of the particles from either smoke source are comprised of semivolatile compounds For tobacco smoke and marijuana smoke, resp., 4350 and 2575 different compounds are detected, of which 670 and 536 (231 in common) are tentatively identified, and of these, 173 and 110 different compounds (69 in common) are known to cause neg. health effects through carcinogenic, mutagenic, teratogenic, or other toxic mechanisms. This study demonstrates striking similarities between marijuana and tobacco smoke in terms of their phys. and chem. properties.

Scientific Reports published new progress about 613-33-2. 613-33-2 belongs to catalysis-chemistry, auxiliary class Benzene, name is 4,4′-Dimethyldiphenyl, and the molecular formula is C14H14, Formula: C14H14.

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

Elsby, Matthew R. published the artcileNickel-Catalyzed C-H Silylation of Arenes with Vinylsilanes: Rapid and Reversible ¦Â-Si Elimination, Recommanded Product: Trimethyl(perfluorophenyl)silane, the publication is Journal of the American Chemical Society (2017), 139(27), 9401-9407, database is CAplus and MEDLINE.

The reaction of C₆F₅H and H₂C:CHSiMe₃ with catalytic [ⁱPr₂Im]Ni(¦Ç²-H₂C:CHSiMe₃)₂ (1b) exclusively forms the C-H silylation product C₆F₅SiMe₃ with ethylene as a byproduct ([ⁱPr₂Im] = 1,3-di(isopropyl)imidazole-2-ylidene). Catalytic C-H bond silylation is facile with partially fluorinated aromatic substrates containing two ortho F substituents adjacent to the C-H bond and 1,2,3,4-tetrafluorobenzene. Less fluorinated substrates react slower. Under the same reaction conditions, catalytic [IPr]Ni(¦Ç²-H₂C:CHSiMe₃)₂ (1a) ([IPr] = 1,3-bis[2,6-diisopropylphenyl]-1,3-dihydro-2H-imidazol-2-ylidene) provided only the alkene hydroarylation product C₆F₅CH₂CH₂SiMe₃. Mechanistic studies reveal that the C-H activation and ¦Â-Si elimination steps are reversible under catalytic conditions with both catalysts 1a and 1b. With catalytic 1a, reversible ethylene loss after ¦Â-Si elimination was also observed despite its inability to catalyze C-H silylation; the reductive elimination step to form the silylation product is much slower than reductive elimination to form the alkene hydroarylation product. Reversible ethylene loss was not observed with 1b, which suggests that the rate-limiting step in the reaction is neither C-H activation nor ¦Â-Si elimination but either ethylene loss or reductive elimination of cis-disposed aryl and SiMe₃ moieties.

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, Recommanded Product: Trimethyl(perfluorophenyl)silane.

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

Hussein, Ahmad Q. published the artcileReactions of ¦Á-bromo isothiocyanates, Safety of 1,1-Dimethylthiourea, the publication is Chemische Berichte (1979), 112(6), 1956-72, database is CAplus.

The reactions of RR¹CBrNCS [I; R = R¹ = Me, RR¹ = (CH₂)₅, R, R¹ = Me₂CH, CO₂Me; Me₃C, Ph; H, Ph; Me₃C, Br] are described. I having ¦Â-H atoms (1st 3 compounds) eliminate HBr to form vinyl isothiocyanates, e.g., CH₂:CMeNCS. H₂O hydrolyzes I to carbonyl compounds RR¹CO. Whereas hard nucleophiles substitute the Br in I, soft nucleophiles add to the C atom of the NCS group. The chem. properties of the products, including heterocycles and geminal diisothiocyanates, are examined Me₂C:NC(S)NMe₂ shows hindered rotation about the C(S)-N and C:N bonds.

Chemische Berichte published new progress about 6972-05-0. 6972-05-0 belongs to catalysis-chemistry, auxiliary class Thiourea,Amine,Aliphatic hydrocarbon chain,Amide, name is 1,1-Dimethylthiourea, and the molecular formula is C3H8N2S, Safety of 1,1-Dimethylthiourea.

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

Singh, Amravati S. published the artcileHighly regioselective tandem hydroformylation of substituted styrene using Iminophosphine rhodium complex immobilized on carbon, Recommanded Product: 3-(Trimethoxysilyl)propan-1-amine, the publication is Journal of Industrial and Engineering Chemistry (Amsterdam, Netherlands) (2022), 218-232, database is CAplus.

Reported the sustainable route for the synthesis of ionic carbon from bio-derived sugarcane-waste (Bagasse) and further anchoring with iminophosphine rhodium complex (Rh@BCNP) and utilized for tandem hydroformylation reaction. The SEM anal. confirmed the formation of spherical shape morphol. of carbon with sizes ranging from 30-150 nm. The successful functionalization of the iminophosphine rhodium complex on the carbon surface were determined by XPS, TEM, FE-SEM, ³¹P NMR, ¹³C CP-MAS-NMR and FTIR anal. Furthermore, ICP-OES anal. confirmed the presence of 0.307 mmoles/g of Rh and 0.484 mmoles/g of P on the carbon surface. Rh@BCNP catalyst was the best combination of triphenylphosphine ligand, imine and rhodium metal, resulting in hybrid material with some acidic properties of carbon that favor the selectivity towards linear products. Rh@BCNP showed remarkable catalytic performance under moderate reaction conditions (80¡ãC, 40 bar (CO + H₂)) in 5 h. This sharp divergence from other methods leading to linear amines and acetals results in a novel atom economic approach to synthesize pharmaceuticals and industrial products. The Rh@BCNP catalyst gave recyclability up to five cycles.

Journal of Industrial and Engineering Chemistry (Amsterdam, Netherlands) published new progress about 13822-56-5. 13822-56-5 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is 3-(Trimethoxysilyl)propan-1-amine, and the molecular formula is C7H6Cl2, Recommanded Product: 3-(Trimethoxysilyl)propan-1-amine.

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