Tag: M.W=200-250

Pei, Chunzhe published the artcileNi-Catalyzed Direct Carboxylation of Aryl C-H Bonds in Benzamides with CO₂, SDS of cas: 20029-52-1, the publication is Advanced Synthesis & Catalysis (2022), 364(3), 493-499, database is CAplus.

The direct carboxylation of inert aryl C-H bond catalyzed by abundant and cheap nickel is still facing challenge. Herein, authors report the Ni-catalyzed direct carboxylation of aryl C-H bonds in benzamides under 1 atm of CO₂ to afford various Me carboxylates or phthalimides, dealing with different post-processing. The reaction displays excellent functional group tolerance and affords moderate to high carboxylation yields under mild conditions. Detail mechanistic studies suggest that a Ni(0)-Ni(II)-Ni(I) catalytic cycle may be involved in this reaction.

Advanced Synthesis & 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, SDS of cas: 20029-52-1.

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

Liu, Xin published the artcileHydrogenative depolymerization of silicon-modified polyureas, Recommanded Product: 4,4-Diaminodicyclohexyl methane, the publication is Chemical Communications (Cambridge, United Kingdom) (2022), 58(35), 5415-5418, database is CAplus and MEDLINE.

Silicon-modified polyureas were depolymerized by hydrogenation in the presence of Ru and Mn catalysts. Yields of up to 84% of the aliphatic diamine and 81% of silicon-containing diamine were achieved with a com. available PNP-Ru catalyst.

Chemical Communications (Cambridge, United Kingdom) 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, Recommanded Product: 4,4-Diaminodicyclohexyl methane.

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

Burgess, Laurence E. published the artcileThe preparation of immunosuppressant SR-31747, Product Details of C13H16O2, the publication is Synthetic Communications (1997), 27(12), 2181-2191, database is CAplus.

The preparation of immunosuppressant SR-31747 was described. Attempts to install a (Z)-allyl amine included Lindlar partial hydrogenation and vinyl stannane methodologies. Ultimately, the Wittig olefination of 3-chloro-4-cyclohexylbenzaldehyde with the ylide derived from β-aminoethyl phosphonium salt [i.e., [2-(cyclohexylethylamino)ethyl]triphenylphosphonium bromide] proved successful.

Synthetic Communications 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, Product Details of C13H16O2.

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

Neunhoeffer, Otto published the artcileSynthesis and nitration of phenylcyclohexane, Safety of 4-Cyclohexylbenzoic acid, the publication is Journal fuer Praktische Chemie (Leipzig) (1932), 95-109, database is CAplus.

In the preparation of phenyleyelohexane (I) the yield is increased with an excess of C₆H₆; thus, 1 mol. cyclohexyl chloride and 3 mols. C₆H₆ give 0.55 mol. I and 0.18 mol. dicyclohexylbenzene (II), while 12 mols. C₆H₆ gives 0.8 mol. I and 0.08 mol. II. Degradation of I with O₃ gives cyclopentylacetic acid, characterized as the amide, m. 149°. Oxidation of II gives terephthalic acid. Nitration of I in Ac₂O with fuming HNO₃ gives a mixture of p- (III) and o-nitrocyclohexylbenzenes (IV), in the ratio 78: 22; III b_0.6 142°, m. 57°; IV b_0.5 113°, m. 45°. Electrolytic reduction of III gives quantitatively p-cyelohexylaniline; through the diazo reaction this gives 90% of pcyclohexyliodobenzene, b_0.5 117°, m. 4°, and 42% of nitrile, b_0.5 123°, m. 41°; hydrolysis gives p-cyclohexylbenzoic acid, m. 196°. Electrolytic reduction of IV gives o-cyclohexylaniline,b_0.6 106°.m.13°; Acderiv.,m.101°; Bzderiv.,m.154°. III is trimorphic, m. 54°, 56° and 57°.

Journal fuer Praktische Chemie (Leipzig) 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, Safety of 4-Cyclohexylbenzoic acid.

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

Neunhoeffer, Otto published the artcileTricyclohexylmethane series. III, SDS of cas: 20029-52-1, the publication is Justus Liebigs Annalen der Chemie (1936), 58-65, database is CAplus.

p-Cyclohexylphenylmagnesium iodide and 13 g. Me p-cyclohexylbenzoate give 3 g. p,p’-dicyclohexylbiphenyl (I), m. 205°; some p,p’-dicyclohexylbenzophenone, m. 135°; and as the principal fraction, tri-(p-cyclohexylphenyl)carbinol (II), m. 168°. The action of CO₂ upon the Grignard reagent gives p-cyclohexylbenzoic acid, I and II. II in concentrated H₂SO₄ gives an intensive red-yellow color; II does not react with the usual reagents to form a halogen derivative or a Me ether. The action of Ag upon tricyclohexylmethyl bromide is complete in about 3 months; the action of K-Na gives dicyclohexylcyclohexylidenemethane, m. 52°. The cyclohexyl residue does not favor the formation of free radicals.

Justus Liebigs Annalen der Chemie 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

Sridhar, Arun Srikanth published the artcileEffect of stoichiometry on crosslinked epoxy resin characteristics: structural heterogeneities, topological defects, properties, free volume and segmental mobility, Category: quinuclidine, the publication is Soft Matter (2022), 18(12), 2354-2372, database is CAplus and MEDLINE.

Exptl. studies have shown that changes in stoichiometry (R, ratio of amine groups to epoxy groups) cause considerable variations in the properties of epoxy-amine systems. Rationales based on free volume concepts have been routinely used to address these variations in properties but have hardly been satisfactorily substantiated. Many of these rationales remain as unverified conjectures to date. Substantiating these rationales will certainly bolster our understanding of the structure-stoichiometry-property relationship, but is difficult, due to inherent challenges involved in unambiguously characterizing the structural heterogeneities induced by changes in stoichiometry (structural heterogeneities include compositional distribution in the functionality of monomers, non-uniform dispersion of elastic chains and topol. defects). The aim of the present work is to gain mol.-level insights into this relationship and to verify the rationales that rely on free volume concepts used for addressing the variations in properties with stoichiometry, with the help of all-atom mol. dynamics (MD) simulations. Five epoxy-amine systems with varying R ranging from 0.4 to 3, including the stoichiometric system (R = 1), were considered for these purposes. The properties of interest namely d., glass transition temperature (T_g) and thermal expansion coefficient in the rubbery state (α_rl) of these systems were predicted. The local structure, fractional free volume and segmental mobility of these systems were then subsequently characterized as a function of stoichiometry and the results were analyzed in detail. The role played by defects in properties and fractional free volume was then investigated. The results revealed significant insights into the compositional distribution of monomers with different functionalities as well as offered insights into the dispersion state and mobility of dangling chains, sols and elastic chains in the systems. Further, strong correlations were found between defect composition, fractional free volume at an elevated temperature (600 K) and thermomech. properties (T_g and α_rl) and it was established that the key mechanism underlying these correlations was the plasticization caused by defects. Anal. based on the rule of mixture models showed that these correlations were found to be in good agreement with the interpretations based on free volume concepts. The results also revealed a strong neg. correlation between fractional free volume at room temperature and defect composition, a phenomenon typically associated with the antiplasticization effect.

Soft Matter 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 C2H2N4O2, Category: quinuclidine.

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

La Scala, John J. published the artcileEffect of methyl and methoxy substituents on dianilines for thermosetting polyimide system, Category: quinuclidine, the publication is High Performance Polymers (2020), 32(7), 801-822, database is CAplus.

4,4-Methylenedianiline (MDA) is widely used in high-temperature polyimide resins, including polymerization of monomer reactants-15. The toxicity of MDA significantly limits the manufacturability using this resin. Modifying the substitution and electronics of MDA could allow for the reduction of toxicity while maintaining the high-performing properties of the materials derived from the modified MDA. The addition of a single Me substituent, methoxy substituent, location of these substituents, and location of the amine relative to the phenolic bridge were modified as were other non-aniline diamines. Various anilines were condensed with paraformaldehyde under acidic conditions to yield dianilines. These dianilines and diamines were reacted with nadic anhydride and 3,3,4,4-benzophenonetetracarboxylic dianhydride in methanol to form the polyamic acid oligomers and heated at elevated temperature to form polyimide oligomers. It was found that the mol. weight of the oligomers derived from MDA alternatives was generally lower than that of MDA oligomers resulting in lower glass transition temperatures (T_gs) and degradation temperatures Addnl., methoxy substituents further reduce the T_g of the polymers vs. Me substituents and reduce the thermal stability of the resin. Methyl-substituted alternatives produced polyimides with similar T_gs and degradation temperatures The toxicity of the MDA alternatives was examined Although a few were identified with reduced toxicities, the alternatives with properties similar to that of MDA also had high toxicities.

High Performance Polymers 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, Category: quinuclidine.

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

Jiang, Yuan published the artcileBiomass-Based Polyureas Derived from Rigid Furfurylamine and Isomannide, Recommanded Product: 4,4-Diaminodicyclohexyl methane, the publication is ACS Applied Polymer Materials (2022), 4(3), 2197-2204, database is CAplus.

Polyureas are important com. polymers that are widely used in construction, automobile industry, military field, and coatings. Biomass-based amines are attractive feedstock in the synthesis of versatile polyureas. Furan-based diamine and isomannide-derived (Im-derived) diamine can be interesting monomers for such materials due to their renewability and intrinsic rigidity, but they have not been extensively studied. Herein, biomass-based polyureas were prepared by polymerizing dicarbamates derived from furfurylamine and isomannide. The dicarbamates were produced in multigram-scale quantities with high purity and yield. A series of polyureas with reasonably high mol. weights were subsequently prepared by condensing the dicarbamates with various diamines. ¹H NMR and ¹³C NMR spectroscopy confirmed the structure of the targeted copolymers. Exploration of thermal behavior by thermogravimetric anal. (TGA) and differential scanning calorimetry (DSC) revealed that the synthetic polyureas showed good thermal stability and glass-transition temperatures (T_g) ranging from 11 to 213°C.

ACS Applied Polymer Materials 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, Recommanded Product: 4,4-Diaminodicyclohexyl methane.

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

Feng, Xiang-Jun published the artcileSynthesis and Immunomodulating Activity of New Analogues of Fingolimod, Name: 4-Cyclohexylbenzoic acid, the publication is Archiv der Pharmazie (Weinheim, Germany) (2012), 345(2), 93-100, database is CAplus and MEDLINE.

Five new immunomodulators I.HCl (R = H, Et, n-Pr, n-Bu, n-Pen) in which a trans-4-alkyl-substituted cyclohexane replaces the flexible C8 alkyl chain of Fingolimod were synthesized. For in-vitro test, the compounds were dissolved in DMSO as a stock solution and diluted to a desired concentration with RPMI 1640 nutrient solution For in-vivo test, the compounds were prepared in pathogen-free saline containing 0.5% DMSO. These new immunomodulators displayed more potent immunoinhibitory activities in vitro and moderate immunomodulating activities in vivo. They show therapeutic effects on DNFB-induced DTH reaction and inhibitory effects on the antigen-specific T-cell proliferation.

Archiv der Pharmazie (Weinheim, Germany) 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, Name: 4-Cyclohexylbenzoic acid.

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

Sim, Jee-Hyun published the artcileExperimental and Digimat-FE Based Representative Volume Element Analysis of Dye-Mixed Colored Resin and Carbon Fiber, Application of 4,4-Diaminodicyclohexyl methane, the publication is Polymers (Basel, Switzerland) (2022), 14(5), 1028, database is CAplus and MEDLINE.

Recently, the automobile industry has demanded weight reduction, so research on materials is being actively conducted. Among this research, carbon fiber-reinforced composite materials are being studied a lot in the automobile industry due to their excellent mech. properties, chem. resistance, and heat resistance. However, carbon fiber-reinforced composite materials have disadvantages, in that they are not free from color selection, and have weak interfacial bonding strength. In this study, a colored epoxy resin was prepared by mixing epoxy-which is a thermosetting resin according to the pigment concentration (0.1, 0.3, 0.5, 1.0 wt%)-and curing shrinkage. Thermal expansion characteristics were analyzed and the concentration of 0.5 wt% pigment showed the lowest shrinkage and thermal expansion characteristics. In addition, to measure the interfacial shear strength (IFSS) of the carbon fiber and the colored epoxy resin, the IFSS was obtained by performing a microdroplet debonding test, and the strength of the pigment concentration of 0.5 wt% was reduced to a relatively low level. Through these experiments, it was determined that an epoxy resin in which 0.5 wt% pigment is mixed is the optimal condition. Finally, using the composite material modeling software (Digimat 2020.0), the representative volume element (RVE) of the meso-scale was set, and interfacial properties of carbon fibers and colored epoxy resins were analyzed by interworking with general-purpose finite element anal. software (Abaqus CAE).

Polymers (Basel, Switzerland) 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 C17H19N3O6, Application of 4,4-Diaminodicyclohexyl methane.

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