Month: December 2022

Sukowski, Verena published the artcileS,O-Ligand Promoted meta-C-H Arylation of Anisole Derivatives via Palladium/Norbornene Catalysis, Application of 1,2-Dimethoxybenzene, the publication is Angewandte Chemie, International Edition (2022), 61(31), e202201750, database is CAplus and MEDLINE.

Here, a new catalytic system based on palladium/norbornene and an S,O-ligand for the meta-C-H arylation of aryl ethers that significantly outperforms previously reported systems has been developed. The unique ability of this system to employ alkoxyarene substrates bearing electron donating and withdrawing substituents is demonstrated. Addnl., ortho-substituted aryl ethers are well tolerated, overcoming the “ortho constraint”, which is the necessity to have a meta-substituent on the alkoxyarene to achieve high reaction efficiency, by enlisting novel norbornene mediators. Remarkably, for the first time the monoarylation of alkoxyarenes is achieved efficiently enabling the subsequent introduction of a second, different aryl coupling partner to rapidly furnish unsym. terphenyls. Further insight into the reaction mechanism was achieved by isolation and characterization of some Pd-complexes-before and after meta C-H activation-prior to evaluation of their resp. catalytic activities.

Angewandte Chemie, International Edition published new progress about 91-16-7. 91-16-7 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether,Inhibitor,Inhibitor,Inhibitor, name is 1,2-Dimethoxybenzene, and the molecular formula is C19H21N, Application of 1,2-Dimethoxybenzene.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Sukowski, Verena published the artcileS,O-Ligand Promoted meta-C-H Arylation of Anisole Derivatives via Palladium/Norbornene Catalysis, SDS of cas: 2944-47-0, the publication is Angewandte Chemie, International Edition (2022), 61(31), e202201750, database is CAplus and MEDLINE.

Here, a new catalytic system based on palladium/norbornene and an S,O-ligand for the meta-C-H arylation of aryl ethers that significantly outperforms previously reported systems has been developed. The unique ability of this system to employ alkoxyarene substrates bearing electron donating and withdrawing substituents is demonstrated. Addnl., ortho-substituted aryl ethers are well tolerated, overcoming the “ortho constraint”, which is the necessity to have a meta-substituent on the alkoxyarene to achieve high reaction efficiency, by enlisting novel norbornene mediators. Remarkably, for the first time the monoarylation of alkoxyarenes is achieved efficiently enabling the subsequent introduction of a second, different aryl coupling partner to rapidly furnish unsym. terphenyls. Further insight into the reaction mechanism was achieved by isolation and characterization of some Pd-complexes-before and after meta C-H activation-prior to evaluation of their resp. catalytic activities.

Angewandte Chemie, International Edition published new progress about 2944-47-0. 2944-47-0 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether, name is 2-Isopropylanisole, and the molecular formula is C9H20Cl2Si, SDS of cas: 2944-47-0.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Kleybolte, Moritz E. published the artcileHigh-Molecular-Weight Bisalkoxy-Substituted Poly(para)phenylenes by Kumada Polymerization, Related Products of ethers-buliding-blocks, the publication is Macromolecules (Washington, DC, United States) (2022), 55(13), 5361-5370, database is CAplus.

Substituted poly(para)phenylenes (PPPs) are conjugated polymers with an attractive application potential in various fields of materials science. They are synthesized nearly exclusively using catalytic cross-coupling polymerization reactions based on Pd- or Ni-catalysts. Among these synthetic approaches to access alkoxy-substituted PPPs, Kumada catalyst transfer polymerization (KCTP or GRIM polymerization) would offer certain economic advantages over Suzuki-type polymerization as it relies on the utilization of a non-precious metal for catalysis. It also results in less total costs of the utilized reagents, avoiding addnl. preparative steps such as synthesis, isolation, and purification of boronic acid derivatives necessary for the Suzuki reaction. In fact, KCTP is nowadays the state-of-the-art method for the synthesis of polythiophenes. However, the application of KCTP for the synthesis of alkoxy-substituted PPPs leads to polymers with low mol. weights, limiting their practical applicability. Here, we developed a synthesis protocol that resulted in MEH-PPP with a mol. weight of M_n = 133 kg/mol and BHex-PPP with M_n = 153 kg/mol relative to polystyrene, outperforming the previous state of the art by a factor more than 5. Also, a tetra(ethylene glycol)-substituted PPP has been prepared by this procedure, with a mol. weight exceeding the previously reported results for analogous structures. Such mol. weights can be obtained in a reasonable reaction time (5 days) using low concentrations of an N-heterocyclic carbene-coordinated Ni complex. The polymerization kinetics suggested a chain-growth mechanism with a chain transfer step. The latter is caused most likely by a bimol. interaction of the Ni-species at the polymer chain ends.

Macromolecules (Washington, DC, United States) published new progress about 146370-51-6. 146370-51-6 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether, name is 1-((2-Ethylhexyl)oxy)-4-methoxybenzene, and the molecular formula is C15H24O2, Related Products of ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Shanmugapriya, Ramasamy published the artcileMetal-chloroglynate ionic liquids: Catalytic application for friedel-crafts [F-C] reactions, HPLC of Formula: 93-04-9, the publication is Journal of the Indian Chemical Society (2021), 98(6), 100081, database is CAplus.

Various metal-containing ionic liquids were used as catalysts for Friedel-Crafts reactions. The reaction of R-X with benzene in the presence of M-IL (M = Fe, Zn, Cd, Cu) along with 1-glycyl-3-methylimidazolium chloride ([Gmim] Cl) ionic liquid, leads to the development of several key intermediates. Among them, metal-iron showed higher catalytic activity without organic solvents. This technique features high yield, a simple product isolation, ILs reusability and reduced waste discharge, thus rendering this catalytic system both effective and natural friendly.

Journal of the Indian Chemical Society published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C10H14O, HPLC of Formula: 93-04-9.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Liu, Yulin published the artcileNovel inhibitors of AChE and Aβ aggregation with neuroprotective properties as lead compounds for the treatment of Alzheimer’s disease, Category: ethers-buliding-blocks, the publication is European Journal of Medicinal Chemistry (2022), 114305, database is CAplus and MEDLINE.

A series of sulfone analogs of donepezil I (R¹ = H, F; R² = H, 4-F, 3-Cl, etc.) were designed and synthesized as novel acetylcholinesterase (AChE) inhibitors with the potent inhibiting Aβ aggregation and providing neuroprotective effects as potential modalities for Alzheimer’s disease (AD). Most of the target compounds displayed effective inhibition of AChE, especially compound II which displayed powerful inhibitory activity (IC₅₀ = 2.4 nM). Kinetic and docking studies indicated that compound II was a mixed-type inhibitor. Furthermore, in glyceraldehyde (GA)-exposed SH-SY5Y differentiated neuronal cells, compound II could potently inhibit AChE, reduce tau phosphorylation at S396 residue, provide neuroprotection by rescuing neuronal morphol. and increasing cell viability. It was also found to reduce amyloid aggregation in the presence of AChE. In addition, compound II showed evident protections from mitochondrial membrane dysfunction and oxidative stress in okadaic acid-induced pharmacol. models. Moreover, compound II exhibited more effective treatment prospects in vivo than donepezil, including a moderate blood-brain barrier permeability, a more potent AChE inhibitory activity and behavioral improvement in scopolamine-induced cognition-impaired mice model at a much lower dose. Collectively, compound II is a promising lead compound for further investigation to discovery and development of new anti-AD agents.

European Journal of Medicinal Chemistry published new progress about 91-16-7. 91-16-7 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether,Inhibitor,Inhibitor,Inhibitor, name is 1,2-Dimethoxybenzene, and the molecular formula is C8H10O2, Category: ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Shishido, Ryosuke published the artcileGeneral Synthesis of Trialkyl- and Dialkylarylsilylboranes: Versatile Silicon Nucleophiles in Organic Synthesis, Category: ethers-buliding-blocks, the publication is Journal of the American Chemical Society (2020), 142(33), 14125-14133, database is CAplus and MEDLINE.

Silylboranes R₃SiBpin were prepared by transition metal-catalyzed borylation of hydrosilanes R₃SiH with pinB-Bpin; versatility of silicon nucleophiles thus obtained is explored in coupling and conjugate addition reactions. Compared to carbon-based nucleophiles, the number of silicon-based nucleophiles that is currently available remains limited, which significantly hampers the structural diversity of synthetically accessible silicon-based mols. Given the high synthetic utility and ease of handling of carbon-based boron nucleophiles, silicon-based boron nucleophiles, i.e., silylboranes, have received considerable interest in recent years as nucleophilic silylation reagents that are activated by transition-metal catalysts or bases. However, the range of practically accessible silylboranes remains limited. In particular, the preparation of sterically hindered and functionalized silylboranes remains a significant challenge. Here, we report the use of rhodium and platinum catalysts for the direct borylation of hydrosilanes with bis(pinacolato)diboron, which allows the synthesis of new trialkylsilylboranes that bear bulky alkyl groups and functional groups as well as new dialkylarylsilylboranes that are difficult to synthesize via conventional methods using alkali metals. We further demonstrate that these compounds can be used as silicon nucleophiles in organic transformations, which significantly expands the scope of synthetically accessible organosilicon compounds compared to previously reported methods. Thus, the present study can be expected to inspire the development of efficient methods for novel silicon-containing bioactive mols. and organic materials with desirable properties. We also report the first ¹¹B{¹H} and ²⁹Si{¹H} NMR spectroscopic evidence for the formation of ⁱPr₃SiLi generated by the reaction of ⁱPr₃Si-B(pin) with MeLi.

Journal of the American Chemical Society published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C16H14O6, Category: ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Hayashi, Kyohei published the artcileMacrocyclic Peptides as a Novel Class of NNMT Inhibitors: A SAR Study Aimed at Inhibitory Activity in the Cell, Product Details of C25H23NO4, the publication is ACS Medicinal Chemistry Letters (2021), 12(7), 1093-1101, database is CAplus and MEDLINE.

Nicotinamide N-methyltransferase (NNMT), which catalyzes the methylation of nicotinamide, is a cytosolic enzyme that has attracted much attention as a therapeutic target for a variety of diseases. However, despite the considerable interest in this target, reports of NNMT inhibitors have still been limited to date. In this work, utilizing in vitro translated macrocyclic peptide libraries, we identified peptide 1 as a novel class of NNMT inhibitors. Further exploration based on the X-ray cocrystal structures of the peptides with NNMT provided a dramatic improvement in inhibitory activity (peptide 23: IC₅₀ = 0.15 nM). Furthermore, by balance of the peptides’ lipophilicity and biol. activity, inhibitory activity against NNMT in cell-based assay was successfully achieved (peptide 26: cell-based IC₅₀ = 770 nM). These findings illuminate the potential of cyclic peptides as a relatively new drug discovery modality even for intracellular targets.

ACS Medicinal Chemistry Letters published new progress about 77128-73-5. 77128-73-5 belongs to ethers-buliding-blocks, auxiliary class Inhibitor, name is (S)-2-((((9H-Fluoren-9-yl)methoxy)carbonyl)(methyl)amino)-3-phenylpropanoic acid, and the molecular formula is C25H23NO4, Product Details of C25H23NO4.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Arai, Kenta published the artcileIntermolecular chemo- and regioselective aromatic C-H amination of alkoxyarenes promoted by rhodium nitrenoids, Formula: C10H14O, the publication is Chemical Communications (Cambridge, United Kingdom) (2018), 54(18), 2264-2267, database is CAplus and MEDLINE.

Intermol. aromatic C(sp²)-H amination promoted by neutral rhodium nitrenoids has been developed. The reactions proceeded with various oxygen-substituted arenes ROR¹ (R = Me, Et, Bn, etc.; R¹ = Ph, 2-fluorophenyl, 2-benzylphenyl, etc.) (1.5 equivalent) in a chemo- and regioselective manner. The aromatic C(sp²)-H amination took place at the para position of the oxygen substituent in the presence of benzylic C(sp³)-H bonds and/or C(sp³)-H bonds α to ethereal oxygen.

Chemical Communications (Cambridge, United Kingdom) published new progress about 2944-47-0. 2944-47-0 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether, name is 2-Isopropylanisole, and the molecular formula is C10H14O, Formula: C10H14O.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Murphy, Jaclyn M. published the artcileOne-Pot Synthesis of Arylboronic Acids and Aryl Trifluoroborates by Ir-Catalyzed Borylation of Arenes, Application In Synthesis of 929626-18-6, the publication is Organic Letters (2007), 9(5), 757-760, database is CAplus and MEDLINE.

The synthesis of arylboronic acids and aryl trifluoroborates in a one-pot sequence by Ir-catalyzed borylation of arenes is reported. To prepare the arylboronic acids, the Ir-catalyzed borylation is followed by oxidative cleavage of the boronic ester with NaIO₄ and to prepare the aryltrifluoroborate, the Ir-catalyzed borylation is followed by displacement of pinacol by KHF₂. These two-step sequences give products that are more reactive toward subsequent chem. than the initially formed pinacol boronates.

Organic Letters published new progress about 929626-18-6. 929626-18-6 belongs to ethers-buliding-blocks, auxiliary class Boronic acid and ester,Benzene,Ester,Boronic Acids,Boronic Acids,Boronic acid and ester, name is (3-(Methoxycarbonyl)-5-methylphenyl)boronic acid, and the molecular formula is C9H11BO4, Application In Synthesis of 929626-18-6.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Castorina, Rosemary published the artcilevolatile organic compound emissions from markers used in preschools, schools, and homes, Formula: C4H10O2, the publication is International Journal of Environmental Analytical Chemistry (2016), 96(13), 1247-1263, database is CAplus.

There is little published research examining volatile organic compound (VOC) emissions from art markers. In this study, we characterised VOC emission rates from markers commonly used by children at home and in school, and by teachers in their classrooms. We developed a method to measure standardised emission rates under controlled laboratory conditions, focusing on four major marker types: permanent, dry erase, highlighter, and washable. Emission rates for other less common marker types were also measured. We conducted addnl. experiments determining changes in emission profiles over short and long time periods (several hours up to daily use over about 2 mo), as well as during periods of active drawing. We tested a total of 101 markers and report emission rates for 60 chems. Permanent and dry erase markers had average total VOC emissions more than 400 times higher than highlighters and washable markers. Alcs. were the most highly emitted class of VOCs from permanent and dry erase markers. Some chems. associated with potentially serious health concerns were also identified. Future studies that employ full-scale chamber experiments and personal monitoring in classrooms to measure children’s actual exposures are recommended.

International Journal of Environmental Analytical Chemistry published new progress about 1589-47-5. 1589-47-5 belongs to ethers-buliding-blocks, auxiliary class Aliphatic hydrocarbon chain,Alcohol,Ether, name is 2-Methoxypropan-1-ol, and the molecular formula is C4H10O2, Formula: C4H10O2.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem