Day: December 7, 2022

Bryson, D. J. published the artcileFar infrared spectra of five-coordinate complexes, Recommanded Product: 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, the publication is Inorganic and Nuclear Chemistry Letters (1969), 5(5), 347-8, database is CAplus.

Examination of the spectra of complexes formed by the ligand 2-pyridine-carboxaldehyde 2′-pyridylhydrazone (paphy) in the region 400-150 cm.-1 indicates that a distinction may probably be made between 4, 5, and 6 coordination because of differences in frequencies of the peaks assignable to metal-halogen vibrations. The metal-halogen frequencies are presented for the 5-coordinate complexes: M(paphy)X2,M = β-Co, Mn, Zn, X = Cl, Br; the octahedral complexes: α-Co(paphy)Cl2, Ni(paphy)Cl2, and Ni-(paphy)Br2; and the tetrahedral pyridine complexes: M(py)2X2, X = Co, Zn, X = Cl, Br.

Inorganic and Nuclear Chemistry Letters published new progress about 2215-33-0. 2215-33-0 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, and the molecular formula is C11H10N4, Recommanded Product: 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Krossing, Ingo published the artcileBis(tetramethylpiperidino)aluminum halide adducts tmp₂AlX.Do and tetrahaloaluminates of tricoordinated aluminum cations [tmp₂Al(Do)]AlX₄, Formula: C23H20BN, the publication is European Journal of Inorganic Chemistry (1998), 927-939, database is CAplus.

Upon treatment with Lewis bases Do (Do = pyridine bases or THF), the Lewis acids tmp₂AlX (X = Cl, Br, I) are converted exclusively to the monoadducts tmp₂AlX.Do. Crystal and mol. structure of these monoadducts were determined The Al-X bonds of these addition compounds are considerably elongated, indicating a tendency towards the formation of ionic species [tmp₂Al(Do)]X. Due to the steric requirements of the bulky tmp ligands, addition of an excess of the Lewis base does not force these compounds to form tetracoordinated Al cations [tmp₂Al(Do)₂]⁺ or pentacoordinated adducts tmp₂AlX.Do₂. Attempts to prepare ionic representatives by reaction of tmp₂AlX.Do with “ate” complexes of comparatively low nucleophilicity [MY = NaBP₄, AgBPh₄, LiB(C₆F₅)₄, AgBF₄, AgOtos] result in phenylation products (e.g. tmp₂AlPh and BPh₃.py) or tetracoordinated addition compounds tmp₂AlY.Do (Y = anion). However, addition of 1 equivalent of AlX₃ (X = Br, I) initiates halide abstraction with formation of the ionic [tmp₂Al(Do)]AlX₄ species, as indicated by ²⁷Al-NMR data and conductivity measurements. Solid [tmp₂Al(py)]AlI₄ decomposes readily into tmpAlI₂ and tmpAlI₂.py. Addition of non-polar aliphatic solvents to solutions of [tmp₂Al(Do)]AlX₄ leads to slow decomposition into tmp₂AlX and AlX₃.Do. This also occurs in polar donor solvents, where compounds AlX₃.Do are favored due to the formation of penta- or hexacoordinated species AlX₃.Do.Solv_n (n = 1, 2). Semiempirical AM1 calculations reveal the gas-phase stability of the tricoordinated bis(tmp)aluminum cation in the salt [tmp₂AlPy]AlCl₄ as the only representative in a series of calculated Al cations [(R₂N)₂A1Py]AlCl₄ (R₂N = Me₂N, Et₂N, iPr₂N, tmp). According to these calculations, the stability of a given cation increases when tetrachloroaluminate is replaced by tetraiodoaluminate. Ab initio calculations were performed on 2 cations [(H₂N)₂Al(Do)]⁺ (Do = NH₃, py) and indicate very short Al-N bond lengths owing to ionic bonding contributions.

European Journal of Inorganic Chemistry published new progress about 971-66-4. 971-66-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene, name is Triphenyl(pyridin-1-ium-1-yl)borate, and the molecular formula is C23H20BN, Formula: C23H20BN.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Wei, Ningyi published the artcileImprovement and suggestion on the problems existing in the betahistine mesilate monograph, SDS of cas: 54856-23-4, the publication is Zhongguo Yaopin Biaozhun (2011), 12(5), 384-386, database is CAplus.

A method for determination of water in betahistine mesilate that was of hygroscopicity and thermal instability was established. HPLC, TLC, DSC purity, and hygroscopicity under varying relative humidity conditions were determined Loss on drying influenced on purity of betahistine mesilate. Determination of water by Karl Fischer should be instead of loss on drying in vacuum at 70 degree method. Loss on drying makes betahistine mesilate degraded. The Karl Fischer method is simple, accurate, and suitable for determination of water.

Zhongguo Yaopin Biaozhun published new progress about 54856-23-4. 54856-23-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Amine,Inhibitor,Inhibitor, name is N-Methyl-2-(pyridin-2-yl)ethan-1-amine dimethanesulfonate, and the molecular formula is C7H13NO2, SDS of cas: 54856-23-4.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Okamura, H. published the artcilePhytotoxic effects of antifouling compounds on nontarget plant species, Application of Triphenyl(pyridin-1-ium-1-yl)borate, the publication is Bulletin of Environmental Contamination and Toxicology (2003), 71(5), 881-886, database is CAplus and MEDLINE.

A battery of bioassays was employed to assess the phytotoxic effects of eight antifouling compounds, i.e., copper pyrithione, Disulfiram, Diuron, KH 101, Sea-Nine 211, Thiram, zinc pyrithione (ZnPT) and Ziram, using non-target freshwater species. The microalga was the most susceptible organism, followed by duckweed and lettuce. The test compounds inhibited algal growth in the following order: Diuron > KH101 > ZnPT > Thiram > Disulfiram > CuPT > Ziram > Sea-Nine 211.

Bulletin of Environmental Contamination and Toxicology published new progress about 971-66-4. 971-66-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene, name is Triphenyl(pyridin-1-ium-1-yl)borate, and the molecular formula is C23H20BN, Application of Triphenyl(pyridin-1-ium-1-yl)borate.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Tagata, Tsuyoshi published the artcilePalladium Charcoal-Catalyzed Suzuki-Miyaura Coupling to Obtain Arylpyridines and Arylquinolines, Category: pyridine-derivatives, the publication is Journal of Organic Chemistry (2003), 68(24), 9412-9415, database is CAplus and MEDLINE.

A phosphine ligand, such as PPh₃ or 2-(dicyclohexylphosphino)biphenyl, is essential for the Pd/C-catalyzed Suzuki-Miyaura coupling of halopyridines and haloquinolines, although it has been reported that the reaction of Ph chlorides can be catalyzed by non-prereduced Pd/C without any additives. In the reactions of bromopyridines, bromoquinolines, 2-chloropyridines, and 2-chloroquinolines, PPh₃ was effective enough to provide coupling products in good yields. However, in the reactions of 3-chloropyridine, 4-chloropyridine, and 6-chloroquinoline, sterically hindered 2-(dicyclohexylphosphino)biphenyl was indispensable as a ligand.

Journal of Organic Chemistry published new progress about 89076-64-2. 89076-64-2 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitro Compound,Benzene, name is 5-Nitro-2-phenylpyridine, and the molecular formula is C5H5BrN2, Category: pyridine-derivatives.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Dong, Yifan published the artcileOrientation dependent molecular electrostatics drives efficient charge generation in homojunction organic solar cells, COA of Formula: C23H20BN, the publication is Nature Communications, database is CAplus and MEDLINE.

Organic solar cells usually utilize a heterojunction between electron-donating (D) and electron-accepting (A) materials to split excitons into charges. However, the use of D-A blends intrinsically limits the photovoltage and introduces morphol. instability. Here, we demonstrate that polycrystalline films of chem. identical mols. offer a promising alternative and show that photoexcitation of α-sexithiophene (α-6T) films results in efficient charge generation. This leads to α-6T based homojunction organic solar cells with an external quantum efficiency reaching up to 44% and an open-circuit voltage of 1.61 V. Morphol., photoemission, and modeling studies show that boundaries between α-6T crystalline domains with different orientations generate an electrostatic landscape with an interfacial energy offset of 0.4 eV, which promotes the formation of hybridized exciton/charge-transfer states at the interface, dissociating efficiently into free charges. Our findings open new avenues for organic solar cell design where material energetics are tuned through mol. electrostatic engineering and mesoscale structural control.

Nature Communications published new progress about 971-66-4. 971-66-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene, name is Triphenyl(pyridin-1-ium-1-yl)borate, and the molecular formula is C23H20BN, COA of Formula: C23H20BN.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

van Winden, Tijn M S published the artcileTocolysis with nifedipine versus atosiban and perinatal outcome: an individual participant data meta-analysis., Name: Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, the publication is BMC pregnancy and childbirth (2022), 22(1), 567, database is MEDLINE.

BACKGROUND: Worldwide, nifedipine and atosiban are the two most commonly used tocolytic agents for the treatment of threatened preterm birth. The aim of this study was to evaluate the effectiveness of nifedipine and atosiban in an individual participant data meta-analysis (IPDMA). METHODS: We investigated the occurrence of adverse neonatal outcomes in women with threatened preterm birth by performing an IPDMA, and sought to identify possible subgroups in which one treatment may be preferred. We searched PubMed, Embase, and Cochrane for trials comparing nifedipine and atosiban for treatment of threatened preterm birth between 24^0/7 and 34^0/7 weeks’ gestational age. Primary outcome was a composite of perinatal mortality and neonatal morbidities including respiratory distress syndrome, intraventricular haemorrhage, periventricular leucomalacia, necrotising enterocolitis, and sepsis. Secondary outcomes included NICU admission, prolongation of pregnancy and GA at delivery. For studies that did not have the original databases available, metadata was used. This led to a two-stage meta-analysis that combined individual participant data with aggregate metadata. RESULTS: We detected four studies (Nâ€?â€?91 women), of which two provided individual participant data (Nâ€?â€?50 women). The composite neonatal outcome occurred in 58/364 (16%) after nifedipine versus 69/359 (19%) after atosiban (OR 0.76, 95%CI 0.47-1.23). Perinatal death occurred in 14/392 (3.6%) after nifedipine versus 7/380 (1.8%) after atosiban (OR 2.0, 95%CI 0.80-5.1). Nifedipine results in longer prolongation of pregnancy, with a 18 days to delivery compared with 10 days for atosiban (HR 0.83 (96% CI 0.69-0.99)). NICU admission occurred less often after nifedipine (46%) than after atosiban (59%), (OR 0.32, 95%CI 0.14-0.75). The sensitivity analysis revealed no difference in prolongation of pregnancy for 48 hours (OR 1.0, 95% CI 0.73-1.4) or 7 days (OR 1.3, 95% CI 0.85-5.8) between nifedipine and atosiban. There was a non-significant higher neonatal mortality in the nifedipine-exposed group (OR 1.4, 95% CI 0.60-3.4). CONCLUSIONS: In this IPDMA, we found no differences in composite outcome between nifedipine and atosiban in the treatment of threatened preterm birth. However, the non-significant higher mortality after administering nifedipine warrants further investigation of the use of nifedipine as a tocolytic drug. STUDY REGISTRATION: We conducted this study according to a prospectively prepared protocol, registered with PROSPERO (the International Prospective Register of Systematic Reviews) under CRD42016024244.

BMC pregnancy and childbirth published new progress about 21829-25-4. 21829-25-4 belongs to pyridine-derivatives, auxiliary class Membrane Transporter/Ion Channel,Calcium Channel, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C9H12O, Name: Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Kato, Tetsuzo published the artcileReaction of chloropicoline 1-oxides in liquid ammonia in the presence of potassium amide, Name: 4-Amino-2-picoline, the publication is Heterocycles (1973), 1(3-4), 233-6, database is CAplus.

3-Chloro-2-picoline 1-oxide was treated with K-NH3 at -33° and the product reduced with Raney Ni to give 4-amino-2-picoline. 4-Chloro-2-picoline 1-oxide similarly gave 3-amino-2-picoline and 4-amino-2-picoline. The products resulted from an intermediate 3,4-pyridyne 1-oxide. 5-Chloro-2-picoline 1-oxide, 6-chloro-2-picoline 1-oxide, 3-chloro-4-picoline 1-oxide, and 2-chloro-4-picoline-1-oxide underwent similar aminations.

Heterocycles published new progress about 18437-58-6. 18437-58-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 4-Amino-2-picoline, and the molecular formula is C6H8N2, Name: 4-Amino-2-picoline.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Lokare, Kapil S. published the artcileIridium complexes bearing a PNP ligand, favoring facile C(sp³)-H bond cleavage, Application In Synthesis of 338800-13-8, the publication is Dalton Transactions (2011), 40(36), 9094-9097, database is CAplus and MEDLINE.

Hydrogen iodide is lost upon reaction of PNP with IrI₃, where PNP = 2,6-bis(di-t-butylphosphinomethyl)pyridine to give crystallog. characterized iridacycle Ir(PNP)^*(I)₂, which reacts with H₂ to give Ir(PNP)(H)(I)₂. Ir(PNP)(Cl)₃ is relatively inert towards the intramol. C-H activation of the tert-butyl’s of the PNP ligand. Ir(PNP)(Cl)₃ was characterized by x-ray crystallog.

Dalton Transactions published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C23H43NP2, Application In Synthesis of 338800-13-8.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Gu, Shunyan published the artcileUse of Ligand Steric Properties to Control the Thermodynamics and Kinetics of Oxidative Addition and Reductive Elimination with Pincer-Ligated Rh Complexes, Safety of 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, the publication is Organometallics (2020), 39(10), 1917-1933, database is CAplus.

Oxidative addition and reductive elimination reactions are central steps in many catalytic processes, and controlling the energetics of reaction intermediates is key to enabling efficient catalysis. Oxidative addition and reductive elimination reactions using (^RPNP)RhX complexes (R = tert-Bu, iso-Pr, mesityl and phenyl; X = Cl, I) were studied to deduce the impact of the size of the phosphine substituents. Using (^RPNP)RhCl as starting material, oxidative addition of MeI was observed to produce (^RPNP)Rh(Me)(I)Cl, which was followed by reductive elimination of MeCl to form (^RPNP)RhI. The thermodn. and kinetics vary with the identity of the substituent R” on P of the PNP ligand. The presence of large steric bulk (e.g., R = tert-Bu, mesityl) on the phosphine favors Rh(I) compared to the presence of two smaller substituents (e.g., R = iso-Pr, phenyl). An Eyring plot for the oxidative addition of MeI to (^tBuPNP)RhCl in THF-d₈ is consistent with a polar two-step reaction pathway, and the formation of [(^tBuPNP)Rh(Me)I]I is also consistent with this mechanism. DFT calculations show steric bulk affects the reaction energies of addition reactions that generate six-coordinate complexes by tens of kcal·mol^-1. Ligand steric bulk has a reduced effect (a few kcal·mol^-1) on S_N2 addition barriers, which only require access to one side of the square plane.

Organometallics published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C23H43NP2, Safety of 2,6-Bis((di-tert-butylphosphino)methyl)pyridine.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem