Tag: M.W=200-250

Hoshi, Takashi published the artcileFirst C₂ Symmetrical Siloles: Synthetic, Structural, and Photophysical Studies of 7-Sila-7H-dibenzo[c,g]fluorenes, Category: catalysis-chemistry, the publication is Organometallics (2000), 19(22), 4483-4487, database is CAplus.

The syntheses of 7-sila-7H-dibenzo[c,g]fluorenes 1 were effected via dilithiation of 2,2′-dibromo-1,1′-binaphthyl (2) followed by cyclization of the resulting dianion with dihalosilanes: Me₂SiCl₂, Ph₂SiCl₂, and Ph₂SiF₂. The x-ray structural anal. of 7-sila-7,7-diphenyl-7H-dibenzo[c,g]fluorene (1b) provided the first geometrical parameters of the 7-sila-7H-dibenzo[c,g]fluorene derivative in which the silole skeleton was twisted in the C₂ sym. conformation due to the significant steric repulsion of the binaphthyl group fixed within the van der Waals radii. The photophys. study and semiempirical PM3 calculation suggested the presence of significant ¦Ò*-¦Ð* conjugation in the LUMO of the 7-sila-7H-dibenzo[c,g]fluorene 1 like a silole.

Organometallics published new progress about 312-40-3. 312-40-3 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Difluorodiphenylsilane, and the molecular formula is C12H10F2Si, Category: catalysis-chemistry.

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

Inada, Akira published the artcileStudies on crude drugs effective on growth of Helicobacter pylori. Growth inhibitors in Kaempferiae Rhizoma, Related Products of catalysis-chemistry, the publication is International Congress Series (1998), 319-326, database is CAplus.

Et 4′-methoxycinnamate and 4′-methoxycinnamic acid were isolated from Kaempferiae Rhizoma (rhizomes of Kaempferia galanga) as growth inhibitors against Helicobacter pylori. The inhibitory effects of related compounds were also examined Structure-activity relationships are discussed.

International Congress Series 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, Related Products of catalysis-chemistry.

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

Sawama, Yoshinari published the artcileH-D Exchange Deuteration of Arenes at Room Temperature, Formula: C13H10F2, the publication is Organic Process Research & Development (2019), 23(4), 648-653, database is CAplus.

Arenes underwent C-H deuteration reactions with D₂O in the presence of Pt/C, Ir/C, or combinations of both catalysts in isopropanol/D₂O under argon at ambient temperature to yield arenes deuterated at the arene C-H bonds.

Organic Process Research & Development published new progress about 457-68-1. 457-68-1 belongs to catalysis-chemistry, auxiliary class Fluoride,Benzene, name is Bis(4-fluorophenyl)methane, and the molecular formula is C13H10F2, Formula: C13H10F2.

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

Ohshita, Joji published the artcileSynthesis of Group 14 Dipyridinometalloles with Enhanced Electron-Deficient Properties and Solid-State Phosphorescence, Application of Difluorodiphenylsilane, the publication is Organometallics (2014), 33(2), 517-521, database is CAplus.

Si- and Ge-bridged bipyridyls were prepared, and their optical and electrochem. properties were studied. They exhibited enhanced electron deficiency and phosphorescence properties in comparison to parent bipyridyl. The single-crystal structure of a dipyridinosilole and results of DFT calculations on models are also described.

Organometallics published new progress about 312-40-3. 312-40-3 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Difluorodiphenylsilane, and the molecular formula is C12H10F2Si, Application of Difluorodiphenylsilane.

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

Nguyen, Suong T. published the artcileLight-Driven Depolymerization of Native Lignin Enabled by Proton-Coupled Electron Transfer, Related Products of catalysis-chemistry, the publication is ACS Catalysis (2020), 10(1), 800-805, database is CAplus.

Here, we report a catalytic, light-driven method for the redox-neutral depolymerization of native lignin biomass at ambient temperature This transformation proceeds via a proton-coupled electron-transfer (PCET) activation of an alc. O-H bond to generate a key alkoxy radical intermediate, which then facilitates the ¦Â-scission of a vicinal C-C bond. Notably, this single-step depolymerization is driven solely by visible-light irradiation, requires no stoichiometric chem. reagents, and produces no stoichiometric waste. This method exhibits good efficiency and excellent selectivity for the activation and fragmentation of the ¦Â-O-4 linkage in the polymer backbone, even in the presence of numerous other PCET-active functional groups. The feasibility of this protocol in enabling the cleavage of the ¦Â-1 linkage in model lignin dimers was also demonstrated. These results provide further evidence that visible-light photocatalysis can serve as a viable method for the direct conversion of lignin biomass into valuable arene feedstocks.

ACS Catalysis published new progress about 22693-41-0. 22693-41-0 belongs to catalysis-chemistry, auxiliary class Other Functionalization Reagent, name is 2,4,6-Triisopropylbenzenethiol, and the molecular formula is C15H24S, Related Products of catalysis-chemistry.

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

Narobe, Rok published the artcileC(sp³)-H Ritter amination by excitation of in-situ generated iodine(III)-BF₃ complexes, Synthetic Route of 457-68-1, the publication is Chemical Communications (Cambridge, United Kingdom) (2022), 58(63), 8778-8781, database is CAplus and MEDLINE.

Visible light excitation of iodine(III)-BF₃ complex enables the formation of carbocations from C(sp³)-H bonds. The complexes were generated catalytically from iodoarene, carboxylate ligand, the oxidizing agent Selectfluor and the Lewis acid BF₃. This modular catalytic system allowed the formation of synthetically valuable amine derivatives without a metal- or photocatalyst.

Chemical Communications (Cambridge, United Kingdom) published new progress about 457-68-1. 457-68-1 belongs to catalysis-chemistry, auxiliary class Fluoride,Benzene, name is Bis(4-fluorophenyl)methane, and the molecular formula is C13H10F2, Synthetic Route of 457-68-1.

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

Kremlev, Mikhail M. published the artcileApproaches to prepare perfluoroalkyl and pentafluorophenyl copper couples for cross-coupling reactions with organohalogen compounds, Product Details of C9H9F5Si, the publication is Dalton Transactions (2015), 44(45), 19693-19699, database is CAplus and MEDLINE.

The reactions of iodoperfluoroalkanes C_nF_2n+1I (n = 2, 3, 4) and BuLi at low temperatures give NMR spectroscopic evidence for LiC_nF_2n+1 which were converted into LiCu(C_nF_2n+1)₂ derivatives upon treatment with 0.5 mol Cu(I) bromide, CuBr. An alternative route to obtain perfluoroorgano Cu couples, Cu(R_f)₂Ag (R_f = n-C₃F₇, n-C₄F₉, C₆F₅) was achieved from the reactions of the corresponding perfluoroorgano Ag(I) reagents, AgR_f, and elemental Cu through redox transmetallations. The composition of the resulting reactive intermediates was studied by ¹⁹F NMR spectroscopy and ESI mass spectrometry. Perfluoro-Pr and perfluoro-Bu Cu-Ag reagents prepared by the oxidative transmetalation route exhibited good properties in C-C bond formation reactions with acid chlorides even under moderate conditions. Substitution of Br directly bound to aromatics for perfluoroalkyl groups was achieved at elevated temperatures, while success in halide substitution reactions using Li Cu couples remained poor.

Dalton Transactions 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, Product Details of C9H9F5Si.

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

Runge, M. Brett published the artcileNew selectivities from old catalysts. Occlusion of Grubbs’ catalysts in PDMS to change their reactions, Synthetic Route of 4141-48-4, the publication is Journal of Organometallic Chemistry (2006), 691(24-25), 5278-5288, database is CAplus.

This article describes new selectivities for Grubbs’ first and second generation catalysts when occluded in a hydrophobic matrix of polydimethylsiloxane (PDMS). Occlusion of catalysts in mm-sized slabs of PDMS is accomplished by swelling with methylene chloride then removing the solvent under vacuum. The catalysts are homogeneously dissolved in PDMS yet remain catalytically active. Many substrates that react by olefin metathesis with Grubbs’ catalysts freely dissolved in methylene chloride also react by olefin isomerization with occluded catalysts. Eleven examples of substrates that exhibit dual reactivity by undergoing olefin isomerization with occluded catalysts and olefin metathesis with catalysts dissolved in methylene chloride are reported. Most of these substrates have olefins with allylic phosphine oxides, carbonyls, or ethers. Control experiments demonstrate that isomerization is occurring in the solvent by decomposition of the catalyst from a ruthenium carbene to a proposed ruthenium hydride. This work was extended by heating occluded Grubbs’ first generation catalyst to 100¡ã in 90% MeOH in H₂O in the presence of various alkenes to transform the Grubbs’ catalyst into an isomerization catalyst for unfunctionalized olefins. This work demonstrates that occlusion of organometallic catalysts in PDMS has important implications for their reactions and can be used as a method to control which reactions they catalyze.

Journal of Organometallic Chemistry 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, Synthetic Route of 4141-48-4.

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

Takacs, James M. published the artcileCatalytic iron-mediated ene carbocyclizations of trienes: enantioselective synthesis of the iridoid monoterpenes (-)-mitsugashiwalactone and (+)-isoiridomyrmecin, SDS of cas: 4141-48-4, the publication is Tetrahedron Letters (1992), 33(3), 317-20, database is CAplus.

The iron-catalyzed cycloisomerization of a chiral (2E,7E)-2,7,9-decatriene derivative e.g. I containing an Me substituent adjacent to the 1,3-diene subunit proceeds with high levels of 1,2-stereoinduction relative to the resident Me-containing stereocenter. The stereochem. of the chiral cyclopentane product II is proven by conversion to (-)-mitsugashiwalactone (III) and to (+)-isoiridomyrmecin (IV).

Tetrahedron Letters 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 C14H14N2O2, SDS of cas: 4141-48-4.

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

Takacs, James M. published the artcileCatalytic iron-mediated triene carbocyclizations: stereoselective five-membered ring forming carbocyclizations, Name: Allyldiphenylphosphine oxide, the publication is Journal of Organic Chemistry (1994), 59(23), 6928-42, database is CAplus.

The full details of studies into the regiochem. and stereochem. of Fe-catalyzed carbocyclizations of 2,7,9-decatriene derivatives to form five-membered carbocyclic ring systems are described. The sense and degree of simple diastereoselection depends upon the (2E/2Z)-alkene geometry. In general, (2E,7E)-trienes are the preferred substrate and give rise to 5-membered ring products in which the 2 newly ring formed substituents have the cis relative stereochem. E.g., treating triene I under the standard reaction conditions (dropwise addition of 3.1 equiv Et₃Al to a cooled (0-5¡ã) solution of triene, 10-20 mol. % Fe(acac)₃ and an equivalent amount of 2,2′-bipyridine in 10 mL C₆H₆ or preferably PhMe) gave > 80% cyclopentane derivative II. The roles of the allylic substituent, the alkene geometry, diene substitution, and the influence of resident stereogenic centers incorporated in the tether chain connecting the reacting 1,3-diene and alkene subunits are discussed.

Journal of Organic Chemistry 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, Name: Allyldiphenylphosphine oxide.

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