Tag: M.W=350-400

Mukherjee, Arup published the artcileManganese-Catalyzed Environmentally Benign Dehydrogenative Coupling of Alcohols and Amines to Form Aldimines and H₂: A Catalytic and Mechanistic Study, Related Products of pyridine-derivatives, the publication is Journal of the American Chemical Society (2016), 138(13), 4298-4301, database is CAplus and MEDLINE.

The catalytic dehydrogenative coupling of alcs. and amines to form aldimines represents an environmentally benign methodol. in organic chem. This has been accomplished in recent years mainly with precious-metal-based catalysts. We present the dehydrogenative coupling of alcs. and amines to form imines and H₂ that is catalyzed, for the first time, by a complex of the earth-abundant Mn. Detailed mechanistic study was carried out with the aid of NMR spectroscopy, intermediate isolation, and X-ray anal.

Journal of the American Chemical Society 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, Related Products of pyridine-derivatives.

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

Vogt, Matthias published the artcileActivation of Nitriles by Metal Ligand Cooperation. Reversible Formation of Ketimido- and Enamido-Rhenium PNP Pincer Complexes and Relevance to Catalytic Design, HPLC of Formula: 338800-13-8, the publication is Journal of the American Chemical Society (2013), 135(45), 17004-17018, database is CAplus and MEDLINE.

The dearomatized complex cis-[Re-(PNP^tBu*)-(CO)₂] (4) undergoes cooperative activation of CN triple bonds of nitriles via [1,3]-addition Reversible C-C and Re-N bond formation in 4 was investigated in a combined exptl. and computational study. The reversible formation of the ketimido complexes (5-7) was observed When nitriles bearing an alpha methylene group are used, reversible formation of the enamido complexes (8 and 9) takes place. The reversibility of the activation of the nitriles in the resulting ketimido compounds was demonstrated by the displacement of p-CF₃-benzonitrile from cis-[Re-(PNP^tBu-N=CPh^pCF3)-(CO)₂] (6) upon addition of an excess of benzonitrile and by the temperature-dependent [1,3]-addition of pivalonitrile to complex 4. The reversible binding of the nitrile in the enamido compound cis-[Re-(PNP^tBu-HNC=CHPh)-(CO)₂] (9) was demonstrated via the displacement of benzyl cyanide from 9 by CO. Computational studies suggest a stepwise activation of the nitriles by 4, with remarkably low activation barriers, involving precoordination of the nitrile group to the Re-(I) center. The enamido complex 9 reacts via β-carbon methylation to give the primary imino complex cis-[Re-(PNP^tBu-HN=CC-(Me)-Ph)-(CO)₂]-OTf 11. Upon deprotonation of 11 and subsequent addition of benzyl cyanide, complex 9 is regenerated and the monomethylation product 2-phenylpropanenitrile is released. Complexes 4 and 9 were found to catalyze the Michael addition of benzyl cyanide derivatives to α,β-unsaturated esters and carbonyls.

Journal of the American Chemical Society 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 C14H12N2S, HPLC of Formula: 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

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

Kim, Jong-Woo published the artcileFlexible and transparent electrochromic displays with simultaneously implementable subpixelated ion gel-based viologens by multiple patterning, HPLC of Formula: 47369-00-6, the publication is Advanced Functional Materials (2019), 29(13), n/a, database is CAplus.

Electrochromic materials reversibly change colors by redox reactions depending on the oxidation states. To utilize electrochromic materials for active-matrix display applications, an electrochromic display (ECD) requires simultaneous implementation of various colors and a fine-pixelation process. Herein, flexible and transparent ECDs with simultaneously implementable subpixelated EC gels by sequential multiple patterning are successfully demonstrated. Ionic liquid-based EC gels of monoheptyl-viologen, diheptyl-viologen (DHV), and diphenyl-viologen (DPV) are used to create the colors of ECDs: magenta, blue, and green, resp. Especially, to realize an improved green color, DHV-DPV composite gels are synthesized. Three EC gels exhibit stable properties without degradation during repetitive operation. Moreover, a transmittance greater than 90% is maintained in a bleached state, which is sufficient for application as a transparent display. The subpixelation process for multicolored-flexible ECDs is designed to facilitate both easy fabrication and rapid operation with various patterns at low cost. The subpixelated EC gels using a film mask can be implemented to a min. size of 200 μm. Furthermore, the subpixelated flexible ECDs exhibit high durability even after 1000 cycles of mech. bending tests at a bending radius of 10 mm. Therefore, these EC materials can be used directly for flexible and transparent active-matrix displays.

Advanced Functional Materials published new progress about 47369-00-6. 47369-00-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Benzene,Organic ligands for MOF materials,Nitrogen containing MOF ligands,Nitrogen containing MOF ligands, name is 1,1′-Diphenyl-[4,4′-bipyridine]-1,1′-diium chloride, and the molecular formula is C22H18Cl2N2, HPLC of Formula: 47369-00-6.

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

Semproni, Scott P. published the artcileFour-Coordinate Cobalt Pincer Complexes: Electronic Structure Studies and Ligand Modification by Homolytic and Heterolytic Pathways, Quality Control of 338800-13-8, the publication is Journal of the American Chemical Society (2014), 136(25), 9211-9224, database is CAplus and MEDLINE.

A family of cobalt chloride, Me, acetylide and hydride complexes bearing both intact and modified tert-Bu substituted bis(phosphino)pyridine pincer ligands has been synthesized and structurally characterized and their electronic structures evaluated. Treatment of the unmodified compounds with the stable nitroxyl radical, TEMPO (2,2,6,6-tetramethylpiperidin-1-yloxidanyl) resulted in immediate H- atom abstraction from the benzylic position of the chelate yielding the corresponding modified pincer complexes, (^tBumPNP)CoX (X = H, CH₃, Cl, CCPh). Thermolysis of the Me and hydride derivatives, (^tBuPNP)CoCH₃ and (^tBuPNP)CoH, at 110° also resulted in pincer modification by H atom loss while the chloride and acetylide derivatives proved inert. The relative ordering of benzylic C-H bond strengths was corroborated by H atom exchange experiments between appropriate intact and modified pincer complexes. The electronic structures of the modified compounds, (^tBumPNP)CoX were established by EPR spectroscopy and DFT computations and are best described as low spin Co(II) complexes with no evidence for ligand centered radicals. The electronic structures of the intact complexes, (^tBuPNP)CoX were studied computationally and bond dissociation free energies of the benzylic C-H bonds were correlated to the identity of the X-type ligand on cobalt where pure σ donors such as hydride and Me produce the weakest C-H bonds. Comparison to a rhodium congener highlights the impact of the energetically accessible one-electron redox couple of the first row metal ion in generating weak C-H bonds in remote positions of the supporting pincer ligand.

Journal of the American Chemical Society 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 0, Quality Control of 338800-13-8.

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

Katakis, D. published the artcilePhotocatalytic splitting of water: increase in conversion and energy storage efficiency, Computed Properties of 47369-00-6, the publication is Journal of Photochemistry and Photobiology, A: Chemistry (1994), 81(2), 103-6, database is CAplus.

The yield of the photocatalytic splitting of water using tris-[1-(4-methoxyphenyl)-2-phenyl-1,2-ethylenodithiolenic-S,S’]tungsten as a photocatalyst-catalyst increases by more than three fold on going from 20 to 70°, and there is no indication that the effect levels off at this temperature The intensity of light (within the error limits of our experiments) does not have an appreciable effect. The nature of the reversible electron acceptor also influences the energy storage efficiency, e.g. 1,1-dibenzyl-4,4′-bipyridinium dichloride gives an energy storage efficiency approx. 10% higher than methylviologen. The energy storage efficiency also depends on the presence of electron donors; if Ph₃N is added, the energy storage efficiency increases by 20%. With EDTA the results are even more spectacular; there is a two-fold increase, but only initially. At longer times the system is unstable. Overall light energy storage efficiencies can be as high as 7%, and the expectations for further improvement are very good.

Journal of Photochemistry and Photobiology, A: Chemistry published new progress about 47369-00-6. 47369-00-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Benzene,Organic ligands for MOF materials,Nitrogen containing MOF ligands,Nitrogen containing MOF ligands, name is 1,1′-Diphenyl-[4,4′-bipyridine]-1,1′-diium chloride, and the molecular formula is C22H18Cl2N2, Computed Properties of 47369-00-6.

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

Arashiba, Kazuya published the artcileA molybdenum complex bearing PNP-type pincer ligands leads to the catalytic reduction of dinitrogen into ammonia, Application In Synthesis of 338800-13-8, the publication is Nature Chemistry (2011), 3(2), 120-125, database is CAplus and MEDLINE.

The synthesis of transition metal-dinitrogen complexes and the stoichiometric transformation of their coordinated dinitrogen into ammonia and hydrazine have been the subject of considerable research, with a view to achieving nitrogen fixation under ambient conditions. Since a single example in 2003, no examples have been reported of the catalytic conversion of dinitrogen into ammonia under ambient conditions. The dimolybdenum-dinitrogen complex bearing PNP pincer ligands was found to work as an effective catalyst for the formation of ammonia from dinitrogen, with 23 equivalent of ammonia being produced with the catalyst (12 equivalent of ammonia are produced based on the molybdenum atom of the catalyst). This is another successful example of the catalytic and direct conversion of dinitrogen into ammonia under ambient reaction conditions. We believe that the results described in this Article provide valuable information with which to develop a more effective nitrogen-fixation system under mild reaction conditions.

Nature Chemistry 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

Itabashi, Takayuki published the artcileEffect of substituents on molybdenum triiodide complexes bearing PNP-type pincer ligands toward catalytic nitrogen fixation, Related Products of pyridine-derivatives, the publication is Dalton Transactions (2019), 48(10), 3182-3186, database is CAplus and MEDLINE.

Molybdenum triiodide complexes bearing various substituted pyridine-based PNP-type pincer ligands were prepared and characterized by x-ray anal. Their catalytic activity was studied toward the reduction of nitrogen gas into ammonia under ambient reaction conditions.

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, Related Products of pyridine-derivatives.

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

Yamashita, Makoto published the artcileA catalytic synthesis of dialkylamines from alkylamines using neopentyl-substituted PNP pincer-iridium complex, Quality Control of 338800-13-8, the publication is Inorganica Chimica Acta (2011), 369(1), 15-18, database is CAplus.

A combination of neopentyl-substituted PNP-iridium complex and NaH could catalyze dimerization of alkylamines to form dialkylamines with the highest activity ever reported. Primary and secondary alkylamines were applicable to the present catalytic reaction. Several mechanistic studies suggested a plausible catalytic cycle. The high activity of catalyst may come from the role of neopentyl groups to make a space around the metal center.

Inorganica Chimica Acta 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 C15H24BN3O2, Quality Control of 338800-13-8.

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