Month: December 2022

Hughes, David L. published the artcileFive-coordinate complexes [MoH(SC₆H₂R₃-2,4,6)₃(PR’Ph₂)] (R = Me or Prⁱ, R’ = Me or Et) and their reactions with nitrogen donors. Crystal structures of [MoH(SC₆H₂Prⁱ₃-2,4,6)₃(C₅H₅N)(PMe₂Ph)], [MoH(NC₅H₄S-2)₂(SC₆H₂Prⁱ₃-2,4,6)(PEtPh₂)] and [PPh₄][MoO(SC₆H₂Prⁱ₃-2,4,6)₄], Product Details of C15H24S, the publication is Journal of the Chemical Society, Dalton Transactions: Inorganic Chemistry (1995), 5-15, database is CAplus.

[MoH(SC₆H₂R₃-2,4,6)₃(PR’Ph₂)] (1) (R = Me or Prⁱ, R’ = Me or Et) were prepared by reaction of HSC₆H₂R₃-2,4,6 with [MoH₄(PR’Ph₂)₄] or trans-[Mo(N₂)₂(Pr’Ph₂)₄]. 1 (R = Prⁱ, R’ = Me) reacted with N-donor ligands L (py, 3-Mepy, 3,5-Me₂py or C₃H₃NS) to give [MoH(SC₆H₂Prⁱ₃-2,4,6)₃L(PMePh₂)] (2). The crystal structure of the analog [MoH(SC₆H₂Prⁱ₃-2,4,6)₃(py)(PMe₂Ph)] showed the compound to have a trigonal girdle of thiolate ligands with the pyridine and PMe₂Ph ligands in essentially apical positions. Reaction of 1 (R = Prⁱ, R’ = Et) with pySH-2 gave the seven-coordinate complex [MoH(SC ₆H₂Prⁱ₃-2,4,6)(pyS-2)₂(PEtPh₂)], shown by x-ray crystallog. to have an essentially pentagonal-pyramidal geometry with the hydride located in the equatorial plane. Spectroscopic data for the compounds are discussed in terms of their structures. 1 (R = Prⁱ, R’ = Et) exchanges hydride for deuteride on treatment with deuterium gas in benzene at 20¡ã. Treatment of 1 (R = Prⁱ, R’ = Me) in MeOH with LiBEt₃H, followed by [PPh₄]Cl, gave [PPh₄][MoO(SC₆H₂Prⁱ₃-2,4,6)₄], shown by x-ray crystallog. to have an anion with square-pyramidal geometry and an apical oxide-ligand.

Journal of the Chemical Society, Dalton Transactions: Inorganic Chemistry 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, Product Details of C15H24S.

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

Cook, Earl W. F. published the artcileSulfur-containing DalPhos ligand variants: synthesis and application in Buchwald-Hartwig amination, Recommanded Product: 4-(2-(Di(adamantan-1-yl)phosphino)phenyl)morpholine, the publication is Canadian Journal of Chemistry (2015), 93(3), 326-333, database is CAplus.

New P,S-DalPhos ligands Ad₂PXSAr (L³-L⁶; Ad = 1-adamantyl, X = 1,2-C₆H₄; Ar = alkylphenyl) and Ad₂PX¹N(CH₂CH₂)₂O (X¹ = 3,2-thiophenediyl) featuring pairings of phosphorus and sulfur donor groups as well as new sulfur-containing analogs of the previously reported P,N-ligands Me-DalPhos and Mor-DalPhos, featuring a 2,3-disubstituted thiophene backbone. Palladium organometallic phosphine-thioether and phosphine-amine complexes were also obtained and characterized. In examining the catalytic performance of these new sulfur-containing ligands in the Buchwald-Hartwig amination of octylamine, aniline, or ammonia with 4-chlorotoluene, noteworthy differences in reactivity behavior relative to Me-DalPhos and Mor-DalPhos were observed

Canadian Journal of Chemistry published new progress about 1237588-12-3. 1237588-12-3 belongs to catalysis-chemistry, auxiliary class Mono-phosphine Ligands, name is 4-(2-(Di(adamantan-1-yl)phosphino)phenyl)morpholine, and the molecular formula is C30H42NOP, Recommanded Product: 4-(2-(Di(adamantan-1-yl)phosphino)phenyl)morpholine.

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

Weise, Christian F. published the artcileOrganocatalytic Access to Enantioenriched Dihydropyran Phosphonates via an Inverse-Electron-Demand Hetero-Diels-Alder Reaction, Recommanded Product: (E)-3-(3-Nitrophenyl)acrylic acid, the publication is Journal of Organic Chemistry (2014), 79(8), 3537-3546, database is CAplus and MEDLINE.

The enantioselective inverse-electron-demand hetero-Diels-Alder reaction of the remote olefin functionality in dienamines was developed by the simultaneous activation of ¦Á,¦Â-unsaturated aldehydes and acyl phosphonates. The dual activation is based on an organocatalyst that activates both the ¦Á,¦Â-unsaturated aldehyde, through dienamine formation, and the acyl phosphonate by H-bonding. The enantioselective reaction gave dihydropyran frameworks with three contiguous stereogenic centers. Different substitution patterns are possible for both the heterodiene and the dienophile, and the target products were obtained in good yields and up to 92% ee. The potential of the reaction is demonstrated by transformation of the products into valuable and complex synthons.

Journal of Organic Chemistry published new progress about 1772-76-5. 1772-76-5 belongs to catalysis-chemistry, auxiliary class Benzenes, name is (E)-3-(3-Nitrophenyl)acrylic acid, and the molecular formula is C10H14O, Recommanded Product: (E)-3-(3-Nitrophenyl)acrylic acid.

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

Reed, Christopher D. published the artcileEvaluation of tetraethylammonium bicarbonate as a phase-transfer agent in the formation of [¹⁸F]fluoroarenes, Name: Tetraethylammonium hydrogencarbonate, the publication is Journal of Fluorine Chemistry (2012), 231-237, database is CAplus.

Tetraethylammonium bicarbonate, Et₄N¡¤HCO₃, was found to be an efficient phase-transfer agent, in a microreactor, for the production of [¹⁸F]fluoroarenes from a range of precursors (diaryliodonium salt, nitroarene and [¹⁹F]fluoroarene). This study has established Et₄N¡¤HCO₃ as a practical alternative to the conventional phase-transfer system – Kryptofix 222/K₂CO₃ – as the radiolabeled products were generated in comparable radiochem. yields. The use of Et₄N¡¤HCO₃ also dramatically increased productivity by eliminating the frequent blockages of the microreactor experienced with the traditional system.

Journal of Fluorine Chemistry published new progress about 17351-61-0. 17351-61-0 belongs to catalysis-chemistry, auxiliary class Phase Transfer Catalyst, name is Tetraethylammonium hydrogencarbonate, and the molecular formula is C9H21NO3, Name: Tetraethylammonium hydrogencarbonate.

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

Ting, Seng Yeat published the artcileLong-chain polyunsaturated fatty acid biosynthesis in a land-crab with advanced terrestrial adaptations: Molecular cloning and functional characterization of two fatty acyl elongases, Name: Docosahexaenoic Acid, the publication is Comparative Biochemistry and Physiology, Part B: Biochemistry & Molecular Biology (2022), 110773, database is CAplus and MEDLINE.

Depending on the presence and activities of the front-end fatty acyl desaturases and elongation of very long-chain fatty acid (Elovl) enzymes, animals have different capacities for long-chain (¡ÝC₂₀) polyunsaturated fatty acids (LC-PUFA) biosynthesis. Successful land colonisation in brachyuran crabs requires a shift towards terrestrial food chain with limited LC-PUFA availability. We cloned and functionally characterised two elovl genes from the purple land crab Gecarcoidea lalandii. The two Elovl contained all the necessary motifs of a typical polyunsaturated fatty acids (PUFA) Elovl and phylogenetically clustered in the Elovl1 and Elovl6 clades, resp. The G. lalandii Elovl1 elongated saturated fatty acids, with low activities towards C20 and C22 PUFA substrates. Moreover, the G. lalandii Elovl6 was particularly active in the elongation of C18 PUFA, although it also recognized monounsaturated fatty acids as substrates for elongation. Collectively, the herein characterised G. lalandii elovl paralogues fulfil all the elongation steps involved in the LC-PUFA biosynthetic pathways. Tissue distribution of the G. lalandii elovl genes, along with the FA composition analyses, suggest the hepatopancreas and gill as key metabolic sites for fatty acid elongation. However, current data suggest that G. lalandii is unable to rely solely on biosynthesis to fulfil LC-PUFA requirements, since front-end desaturase appears to be absent in this species and other decapods.

Comparative Biochemistry and Physiology, Part B: Biochemistry & Molecular Biology published new progress about 6217-54-5. 6217-54-5 belongs to catalysis-chemistry, auxiliary class Alkenyl,Carboxylic acid,Aliphatic hydrocarbon chain,Metabolic Enzyme,RAR/RXR,Natural product, name is Docosahexaenoic Acid, and the molecular formula is C2H8Cl2N4S2, Name: Docosahexaenoic Acid.

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

Zhang, Zhengxing published the artcileSynthesis and evaluation of ¹⁸F-labeled 4-nitrobenzyl derivatives for imaging tumor hypoxia with positron emission tomography: Comparison of 2-[¹⁸F]fluoroethyl carbonate and 2-[¹⁸F]fluoroethyl carbamate, Recommanded Product: Tetrabutylammonium hydrogencarbonate, the publication is Bioorganic & Medicinal Chemistry Letters (2016), 26(2), 584-588, database is CAplus and MEDLINE.

Two 4-nitrobenzyl derivatives, 2-fluoroethyl 4-nitrobenzyl carbonate 1 and 4-nitrobenzyl N-2-fluoroethyl carbamate 2, were radiolabeled with ¹⁸F and evaluated for imaging tumor hypoxia with positron emission tomog. Although good tumor uptake was observed for [¹⁸F]1 and [¹⁸F]2 (>2.5%ID/g at 3-h post-injection), the tracers cleared slowly from nontarget tissues (>1.5%ID/g) and exhibited extensive defluorination in vivo (>4.0%ID/g for bone). Therefore, [¹⁸F]1 and [¹⁸F]2 are not suitable for imaging tumor hypoxia due to suboptimal tumor-to-background contrasts.

Bioorganic & Medicinal Chemistry Letters published new progress about 17351-62-1. 17351-62-1 belongs to catalysis-chemistry, auxiliary class Salt,Amine, name is Tetrabutylammonium hydrogencarbonate, and the molecular formula is C18H23N3O4S, Recommanded Product: Tetrabutylammonium hydrogencarbonate.

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

Latosinska, J. N. published the artcileNature of Isomerism of Solid Isothiourea Salts, Inhibitors of Nitric Oxide Synthases, As Studied by ¹H-¹⁴N Nuclear Quadrupole Double Resonance, X-ray, and Density Functional Theory/Quantum Theory of Atoms in Molecules, Name: 1,1-Dimethylthiourea, the publication is Journal of Physical Chemistry A (2012), 116(5), 1445-1463, database is CAplus and MEDLINE.

Isothioureas, inhibitors of nitric oxide synthases, have been studied exptl. in solid state by nuclear quadrupole double resonance (NQDR) and X-ray methods and theor. by the quantum theory of atoms in mols./d. functional theory. Resonance frequencies on ¹⁴N have been detected and assigned to particular nitrogen sites in each mol. The crystal packings of (S)-3,4-dichlorobenzyl-N-methylisothiouronium chloride with the disordered chlorine positions in benzene ring and (S)-butyloisothiouronium bromide have been resolved in X-ray diffraction studies. ¹⁴N NQDR spectra have been found good indicators of isomer type and strength of intra- or intermol. N-H¡¤¡¤¡¤X (X = Cl, Br) interactions. From among all salts studied, only for (S)-2,3,4,5,6-pentabromobenzylisothiouronium chloride are both nitrogen sites equivalent, which has been explained by the slow exchange. This unique structural feature can be a key factor in the high biol. activity of (S)-2,3,4,5,6-pentabromobenzylisothiouronium salts.

Journal of Physical Chemistry A 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, Name: 1,1-Dimethylthiourea.

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

Cragg, R. Harry published the artcileContributions to Group IV organometallic chemistry. VII. The effect of electronegativity on substituent shifts in silicon-29 NMR, Synthetic Route of 312-40-3, the publication is Journal of Organometallic Chemistry (1984), 277(2), 199-201, database is CAplus.

Silicon-29 NMR shifts for silanes Me_2-nPh_nSiX₂ (X = H, Me, Ph, F, Cl, NR₂, OR; R = Me, Et, CHMe₂, Ph) indicate that the shifts on replacement of a Me by a Ph group are largely determined by the electronegativity and donor ability of X.

Journal of Organometallic Chemistry 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, Synthetic Route of 312-40-3.

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