Day: November 21, 2022

Koshel’, G. N. published the artcileLiquid-phase catalytic oxidation of methyl derivatives of biphenyl, Quality Control of 20029-52-1, the publication is Kinetics and Catalysis (2004), 45(6), 821-825, database is CAplus.

Liquid-phase catalytic oxidation into acids by air was studied for the following hydrocarbons: isomers of cyclohexyltoluenes and cyclohexyl derivatives of para-xylene, mesitylene, pseudocumene, cyclopentyltoluene, cyclohexyladamantane, 4-methylbiphenyl, 2,4-, 2,5- and 3,4-dimethylbiphenyls, hydroxymethylbiphenyls, and hydroxymethylbenzenes. The oxidation of cyclohexyltoluenes involves a Me group and proceeds without participation of the α-CH bond of the cyclohexyl fragment in the oxidative conversions. The reactivity of the hydrocarbons increases in the order ortho < meta < para. Consecutive conversions of the Me groups to carboxyls occur during the oxidation of dimethylbiphenyls. In 3,4- and 2,5-dimethylbiphenyls, the Me groups in the para and ortho positions, resp., are first oxidized, whereas the reactivity of both of the Me groups in 2,4-dimethylbiphenyl is virtually the same. The mechanism of the oxidation of hydroxymethylbiphenyls and hydroxymethylbenzenes involves the formation of an unstable cation radical, which is then stabilized by emitting a proton, giving hydroxybenzyl, a more stable radical.

Kinetics and Catalysis published new progress about 20029-52-1. 20029-52-1 belongs to quinuclidine, auxiliary class Carboxylic acid,Benzene, name is 4-Cyclohexylbenzoic acid, and the molecular formula is C13H16O2, Quality Control of 20029-52-1.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Schmidt, Philipp published the artcileFormation of a Thiol-Ene Addition Product of Asthma Medication Montelukast Caused by a Widespread Tin-Based Thermal Stabilizer, Synthetic Route of 162515-68-6, the publication is Chemical Research in Toxicology (2020), 33(12), 2963-2971, database is CAplus and MEDLINE.

We report the formation and characterization of two diastereomeric thiol-ene addition products of the asthma medication Montelukast within chewing tablets. Widespread tin-based thermal stabilizers dioctyltin bis(2-ethylhexyl thioglycolate) and monooctyltin tris(2-ethylhexyl thioglycolate), used in the manufacturing process of the medication’s forming foil, were identified as the source of the thiol reactant, showing that these stabilizers may play a part in the degradation of Montelukast and APIs with functionalities similar to those of Montelukast, which should be considered during development of medication. The isolation and anal. of these impurities was performed by HPLC and UV-vis spectroscopy. HRMS and NMR data were collected to characterize and determine the structures of these compounds

Chemical Research in Toxicology published new progress about 162515-68-6. 162515-68-6 belongs to quinuclidine, auxiliary class Thiol,Carboxylic acid,Aliphatic cyclic hydrocarbon, name is 2-(1-(Mercaptomethyl)cyclopropyl)acetic acid, and the molecular formula is C6H10O2S, Synthetic Route of 162515-68-6.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Voronenkov, V. V. published the artcileSynthesis of p-alkylbenzoic acids by one-electron oxidation of p-alkyltoluenes. MINDO/3 calculations of p-alkyltoluenes and their radical cations, Application In Synthesis of 20029-52-1, the publication is Zhurnal Organicheskoi Khimii (1989), 25(12), 2565-9, database is CAplus.

The role of σ,π-conjugation in determining the regiochem. of one-electron oxidation of the title compounds, i.e., p-MeC₆H₄CHMe₂, was investigated by MINDO/3 mol.-structure calculation The isopropyl-group C-H bond was in the plane of the aromatic ring, a conformation preventing its participation in σ,π-conjugation; two of the Me-group C-H bonds were perpendicular to the aromatic plane, however, suggesting their participation in σ,π-conjugation could significantly enhance their acidity and deprotonation affinity. Analogous results were obtained for p-cyclopropyltoluene.

Zhurnal Organicheskoi Khimii published new progress about 20029-52-1. 20029-52-1 belongs to quinuclidine, auxiliary class Carboxylic acid,Benzene, name is 4-Cyclohexylbenzoic acid, and the molecular formula is C5H11NO2S, Application In Synthesis of 20029-52-1.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Doering, W. v. E. published the artcileSynthesis of substituted tropolones, SDS of cas: 20029-52-1, the publication is Journal of the American Chemical Society (1953), 297-303, database is CAplus.

By photochem. decomposition of CH₂N₂ (I) in a substituted benzene (Ia) and oxidation of the resulting tropilidene (II) with KMnO₄, β- (III) and γ- iso-Pr-(IV), β- (V) and γ-cyclohexyl- (VI), 4,5-tetramethylene- (VII), and β- (VIII) and γ-phenyltropolone (IX) were prepared and assigned structures partly on the basis of rearrangement to the related benzoic acids. II were prepared by adding 105 g. nitrosomethylurea (X) in small portions with vigorous stirring at 0° to a mixture of 2-2.5 l. of Ia and 210 mL. 45% KOH, decanting the organic solution, drying 2 h. at 0° over KOH, irradiating with G. E. reflector sunlamps until N evolution ceased (18-42 h.), and distilling the Ia through a 17-plate column. Recovered Ia was recycled; the residues from several runs were combined and distilled through a 35-plate column to give crude II. Equimolar amounts of II and maleic anhydride refluxed 15-24 h. in 5-40 mL. dry C₆H₆ gave the following adducts (XI). The following II [R, yield (% based on X), b.p., n²⁵_D, m.p. and crude yield (%) of the XI] were prepared: iso-Pr (XII), 16.5, 172-5°, 1.4932-1.5020, 115-16°, 17; cyclohexyl (XIII), 13.3, 125.5-8° (20 mm.), 1.5245-1.5300, 201-2°, 11.3; and Ph (XIV), 8.9, 114-16° (6 mm.), 1.6164-1.6213, 131-2°, 22; also 1,2-tetramethylenetropilidene (XV), 20.0, 105-8° (27 mm.), 1.5525-1.5458, 124-5°, 11. II were oxidized by cooling 0.1 mol in 1.4 l. 95% EtOH and 60 mL. 45% KOH to -10° and adding 31.2 g. KMnO₄ in 1.4 l. H₂O over a period of 2-2.5 h. with cooling to -5°. The MnO₂ was filtered, washed with 1 l. hot H₂O, the filtrate added to the washings from which EtOH had been distilled, the solution extracted with CHCl₃, acidified with 6N H₂SO₄, extracted with CHCl₃, and the tropolone (XVI) in this extract converted to the Cu salt (XVII) with saturated aqueous Cu(OAc)₂; the CHCl₃ solutions (XVIII) of XVII obtained by repeated extraction with warm CHCl₃ were concentrated and treated as described for the individual XVI. XVIII from 13.4 g. XII concentrated to 5 mL. and cooled gave 1.22 g. XVII, m. 92-4° after crystallization from CHCl₃ (0.76 g. recovered) (from the mother liquors another 0.229 g., m. 89-91°, was obtained). A CHCl₃ solution of this treated with H₂S (cf. C.A. 46, 487f) gave 0.372 g. crude III, m. 51-2° after sublimation at 60-70° (4 mm.) and crystallization from isohexane (p-nitrobenzoate, m. 119°; α,α’-dibromo derivative, m. 132-3°); material from the second crop of XVII and mother liquors raised the yield to 2.9%. III (0.328 g.), 8 mL. dry C₆H₆, and 0.3 mL. SOCl₂ refluxed until a drop gave no color with alc. FeCl₃, concentrated, and distilled twice at 95-100° (2 mm.) gave 50% 2-chloro-4(or 6)-isopropyltropone, alk. rearrangement of which [cf. D. and K., J. Am. Chem. Soc. 74, 5683(1952)] gave 38% 3-iso-PrC₆H₄CO₂H. IV, obtained in 1.3% yield from the mother liquors from crystallization of the XVII of III, m. 80-1° [p-nitrobenzoate, m. 135°; α,α’-diBr derivative (α,α’-dibromo-γ-thujaplicin), m. 146°]; hydrogenation in 95% EtOH over PtO₂ gave 60% 5-isopropyl-1,2-cycloheptanediol, m.85-6°; treatment with SOCl₂ as for III gave 40% 2-chloro-5-isopropyltropone, which rearranged with alkali to give 17% p-iso-PrC₆H₄CO₂H. The mixed XVII of V and VI, m. 168-71° (4% yield) did not sep. on crystallization from CHCl₃; the oil obtained by H₂S treatment, sublimed at 80-90° (2 mm.) and the sublimate crystallized rapidly gave VI, m. 97-8° (p-nitrobenzoate, m. 160-1°); hydrogenation of this gave 5-cyclohexyl-1,2-cycloheptanediol, m. 123-5°; the Me ether (from VI and CH₂N₂) heated 12 h. at 120° in a sealed tube with 4 mL. absolute MeOH and 0.05 g. NaOMe gave p-cyclohexylbenzoic acid, m. 197-8°. V, m. 88-9° (p-nitrobenzoate, m. 139-40°), was recovered from the mother liquor from VI; hydrogenation gave 4-cyclohexyl-1,2-cycloheptanediol (colorless glass); the Me ether (from V and CH₂N₂) rearranged to m-cyclohexylbenzoic acid, m. 197-8°. Yields of VI and V were raised to 0.21 and 0.13% resp., based on X, by working up the mother liquors. Procedures like those above gave the following XVI [with XVI, m.p., yield (% based on X), p-nitrobenzoate m.p., XVII m.p., hydrogenation product and its m.p., Me ether m.p., Me ether rearrangement product, and its m.p. given]: VII, 130°, 0.62, 149-50.5°, 287-8°, 4,5-tetramethylene-1,2-cycloheptanediol, 74-5°, 59-65° (mixture of isomeric ethers), 5,6,7,8-tetrahydro-2-naphthoic acid, 153-4° (amide, m. 136-8°); VIII, 97°, 0.18, 144-5°, -, 4-phenyl-1,2-cycloheptanediol, 107-9°, Me ether not prepared (rearrangement of 2-chloro-4-phenyltropone, from VIII and SOCl₂, gave diphenyl-3-carboxylic acid, m. 165-6°); IX, 125-6°, 0.09, 220-1°, 342-5° (decomposition), 5-phenyl-1,2-cycloheptanediol, 97-8°, 141° (Me ether not rearranged; rearrangement of 2-chloro-5-phenyltropone, m. 158°, from IX and SOCl₂, gave diphenyl-4-carboxylic acid, m. 223-4°). UV absorption spectra of XVI are given.

Journal of the American Chemical Society published new progress about 20029-52-1. 20029-52-1 belongs to quinuclidine, auxiliary class Carboxylic acid,Benzene, name is 4-Cyclohexylbenzoic acid, and the molecular formula is C13H16O2, SDS of cas: 20029-52-1.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Larini, Paolo published the artcileOn the Mechanism of the Palladium-Catalyzed β-Arylation of Ester Enolates, Recommanded Product: 2′-(Dicyclohexylphosphino)-N2,N2,N6,N6-tetramethyl-[1,1′-biphenyl]-2,6-diamine, the publication is Chemistry – A European Journal (2012), 18(7), 1932-1944, S1932/1-S1932/163, database is CAplus and MEDLINE.

The palladium-catalyzed β-arylation of ester enolates with aryl bromides was studied both exptl. and computationally. First, the effect of the ligand on the selectivity of the α/β-arylation reactions of ortho- and meta-fluorobromobenzene was described. Selective β-arylation was observed for the reaction of o-fluorobromobenzene with a range of biarylphosphine ligands, whereas α-arylation was predominantly observed with m-fluorobromobenzene for all ligands except DavePhos, which gave an approx. 1:1 mixture of α-/β-arylated products. Next, the effect of the substitution pattern of the aryl bromide reactant was studied with DavePhos as the ligand. We showed that electronic factors played a major role in the α/β-arylation selectivity, with electron-withdrawing substituents favoring β-arylation. Kinetic and deuterium-labeling experiments suggested that the rate-limiting step of β-arylation with DavePhos as the ligand was the palladium-enolate-to-homoenolate isomerization, which occurs by a βH-elimination, olefin-rotation, and olefin-insertion sequence. A dimeric oxidative-addition complex, which was shown to be catalytically competent, was isolated and structurally characterized. A common mechanism for α- and β-arylation was described by DFT calculations With DavePhos as the ligand, the pathway leading to β-arylation was kinetically favored over the pathway leading to α-arylation, with the palladium-enolate-to-homoenolate isomerization being the rate-limiting step of the β-arylation pathway and the transition state for olefin insertion its highest point. The nature of the rate-limiting step changed with PCy₃ and PtBu₃ ligands, and with the latter, α-arylation became kinetically favored. The trend in selectivity observed exptl. with differently substituted aryl bromides agreed well with that observed from the calculations The presence of electron-withdrawing groups on these bromides mainly affected the α-arylation pathway by disfavoring CC reductive elimination. The higher activity of the ligands of the biaryldialkylphosphine ligands compared to their corresponding trialkylphosphines could be attributed to stabilizing interactions between the biaryl backbone of the ligands and the metal center, thereby preventing deactivation of the β-arylation pathway.

Chemistry – A European Journal published new progress about 1160556-64-8. 1160556-64-8 belongs to quinuclidine, auxiliary class Mono-phosphine Ligands, name is 2′-(Dicyclohexylphosphino)-N2,N2,N6,N6-tetramethyl-[1,1′-biphenyl]-2,6-diamine, and the molecular formula is C28H41N2P, Recommanded Product: 2′-(Dicyclohexylphosphino)-N2,N2,N6,N6-tetramethyl-[1,1′-biphenyl]-2,6-diamine.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Boisaubert, Pierre published the artcilePhoto-crosslinked Non-Isocyanate Polyurethane Acrylate (NIPUA) coatings through a transurethane polycondensation approach, Quality Control of 1761-71-3, the publication is Polymer (2020), 122855, database is CAplus.

A transurethane polycondensation pathway was used to produce acrylate terminated non-isocyanate polyurethane (NIPUA) oligomers (A-Ol) with controlled mol. weights and chem. structures. These compounds were then photocrosslinked under UV radiations to afford several NIPU acrylate coatings. The influence of the content in urethane functions as well as the chem. structures on the thermal and mech. properties of the final coatings was demonstrated. The obtained coatings exhibited thermal stabilities above 255°C, Young modulus ranging from 2.6 to 9.2 MPa, tensile strength up to 11.8 MPa and elongation at break varying from 20 to 520%.

Polymer published new progress about 1761-71-3. 1761-71-3 belongs to quinuclidine, auxiliary class Ploymers, name is 4,4-Diaminodicyclohexyl methane, and the molecular formula is C13H26N2, Quality Control of 1761-71-3.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Boisaubert, Pierre published the artcilePolyurethane coatings from formulations with low isocyanate content using a transurethane polycondensation route, Related Products of quinuclidine, the publication is Polymer (2022), 124522, database is CAplus.

A strategy aiming to decrease the amount of isocyanate in the PU industries without changing their current facilities is proposed. Hydroxyl terminated non-isocyanate polyurethane (NIPU) oligomers (H-Ol) with controlled mol. weights and chem. structures have been prepared as precursors. They were prepared by transurethane polycondensation between bis(methylcarbamate) (BMC), hydroxyterminated poly(tetramethyleneoxide) (PTMO) and butanediol at several molar ratios. H-Ol were then reacted with a polyisocyanurate as crosslinking agent to afford several partially NIPU coatings. Polyurethanes based on the PTMO polyols and the polyisocyanurate were also prepared as controls to highlight the importance of the urethane function in the H-Ol. The influence of the chem. structures on the thermal and mech. properties of the final coatings has been investigated. The prepared coatings displayed thermal stabilities above 200°C, Young modulus ranging from 3 to 64 MPa, tensile strength values from 0.9 to 17 MPa and elongation at break varying from 25 to 530%. H-Ol with the highest urethane content gave a coating with the best adhesion properties on a metal surface. All the obtained properties were within the characteristic range of two com. PU reference coatings.

Polymer published new progress about 1761-71-3. 1761-71-3 belongs to quinuclidine, auxiliary class Ploymers, name is 4,4-Diaminodicyclohexyl methane, and the molecular formula is C13H26N2, Related Products of quinuclidine.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Tian, Yazhou published the artcileA resveratrol-based epoxy resin with ultrahigh T_g and good processability, Quality Control of 1761-71-3, the publication is European Polymer Journal (2021), 110282, database is CAplus.

Preparing and designing an epoxy system with ultrahigh glass transition temperature (T_g > 300°C) is always a big challenge, which restrict its applications in some cutting-edge areas such as aerospace engineering and elec. electronics. Herein, a biomass-based epoxy resin (REEP) was prepared from resveratrol, and then curing behavior, thermal-mech. properties, mech. performance, thermal stability, dielec. properties and optical properties of REEP/HDDM, REEP/DGEBA/HDDM and DGEBA/HDDM were resp. studied systematically. Results suggested that the T_g of REEP/HDDM was above 320°C, higher than those of most reported epoxy systems, both derived from biomass-based and petroleum-based materials. Moreover, the tensile strength of REEP/HDDM, REEP/DGEBA/HDDM and DGEBA/HDDM were 77.8 MPa, 70.8 MPa and 63.6 MPa, resp., and the T_d5% of REEP/HDDM, REEP/DGEBA/HDDM and DGEBA/HDDM were 319.9°C, 335.1°C and 348.1°C, resp., indicating excellent mech. performance and thermal stability of the cured epoxy system. Interestingly, the REEP/HDDM exhibited outstanding blocking properties in the range of 220-400 nm (UV-light) and low flammability with compact and continuous char residues. In short, REEP, with a well-defined chem. structure, has a stiffness conjugated stilbene structure to prevent the mol. from motioning in the crosslinked network structure and three epoxy groups, thereby increasing the crosslinked d. dramatically, which endows REEP/HDDM network with outstanding comprehensive properties.

European Polymer Journal published new progress about 1761-71-3. 1761-71-3 belongs to quinuclidine, auxiliary class Ploymers, name is 4,4-Diaminodicyclohexyl methane, and the molecular formula is C6H13BO3, Quality Control of 1761-71-3.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Wang, Qin published the artcileInhibitory effects of benzoic acid derivatives on polyphenol oxidase from Pieris rapae, COA of Formula: C13H16O2, the publication is Xiamen Daxue Xuebao, Ziran Kexueban (2006), 45(3), 428-431, database is CAplus.

The title polyphenol oxidase was extracted from the 5th instar of Pieris rapae in present paper. The effects of benzoic acid derivatives on the catalysis activity of polyphenol oxidase for the oxidation of L-dopa were investigated, including terephthalaldhydic acid (a), p-methoxybenzoic acid (b), p-isopropylbenzoic acid (c), p-cyclohexylbenzoic acid (d), p-chlorobenzoic acid (e), p-fluorobenzoic acid (f), and p-bromobenzoic acid (g). The IC₅₀ of a, b, c, d and f were 10.63, 12.22, 1.75, 2.10 and 6.64 mmol/L, resp., while e and g without obvious inhibitory effects. The study results of inhibitory kinetics showed that a, c and f were competitive inhibitors, while b and d were noncompetitive ones. Their inhibition constants were determined and compared. Obviously, the inhibitory effects of c and d were higher than the other compounds, so they might have the bright prospect in the future as the insecticide.

Xiamen Daxue Xuebao, Ziran Kexueban published new progress about 20029-52-1. 20029-52-1 belongs to quinuclidine, auxiliary class Carboxylic acid,Benzene, name is 4-Cyclohexylbenzoic acid, and the molecular formula is C11H10O, COA of Formula: C13H16O2.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider

Wang, Wentao published the artcileMultifunctional and High Affinity Polymer Ligand that Provides Bio-Orthogonal Coating of Quantum Dots, Synthetic Route of 1353016-70-2, the publication is Bioconjugate Chemistry (2016), 27(9), 2024-2036, database is CAplus and MEDLINE.

The authors detail the design of hydrophilic metal-coordinating ligands and their use for the effective coating of luminescent quantum dots. The ligand design exploits the specific, reagent-free nucleophilic addition reaction of amine-modified mols. toward maleic anhydride to introduce several lipoic acid metal-anchors, hydrophilic zwitterion moieties and specific reactive groups along a poly(isobutylene-alt-maleic anhydride) (PIMA) chain. Tunable reactive groups tested in this study include azide, biotin, carboxyl, and amine. Cap exchange with these multi-lipoic acid ligands via a photochem. ligation strategy yields homogeneous QD dispersions that are colloidally stable over several biol.-relevant conditions and for extended periods of time. The zwitterionic coating yields compact nanoparticle size and imparts non-sticky surface properties onto the QDs, preventing protein absorption. The introduction of a controllable number of reactive groups allows conjugation of the QDs to biomols. via bio-orthogonal coupling chemistries including: (1) attachment of the neurotransmitter dopamine to QDs via amine-isothiocyanate reaction to produce a platform capable of probing interactions with cysteine in proteins, based on charge transfer interactions; (2) self-assembly of biotinylated QDs with streptavidin-dye; (3) ligation of azide-functionalized QDs to cyclooctyne-modified transferrin via copper-free click chem. for intracellular delivery. This ligand design strategy can be used to prepare an array of metal-coordinating ligands adapted for coating other inorganic nanoparticles, including magnetic and plasmonic nanomaterials.

Bioconjugate Chemistry published new progress about 1353016-70-2. 1353016-70-2 belongs to quinuclidine, auxiliary class Other Aromatic Heterocyclic,Carboxylic acid,Amide,Inhibitor,Inhibitor, name is Dbco-acid, and the molecular formula is C8H11BO2, Synthetic Route of 1353016-70-2.

Referemce:
https://en.wikipedia.org/wiki/Quinuclidine,
Quinuclidine | C7H13N | ChemSpider