Month: October 2022

Schmidt, Olivia P.; Blackmond, Donna G. published the artcile< Temperature-Scanning Reaction Protocol Offers Insights into Activation Parameters in the Buchwald-Hartwig Pd-Catalyzed Amination of Aryl Halides>, HPLC of Formula: 401-78-5, the main research area is temperature scanning reaction protocol Buchwald Hartwig amination activation parameter.

A temperature-scanning reaction (TSR) protocol allows deconvolution of the driving forces of concentration and temperature in a single experiment, demonstrated here for the Buchwald-Hartwig amination reaction using different amine substrates that exhibit different rate-determining steps. An Eyring anal. reveals that the observed reactivity differences between 1-hexylamine and benzophenone hydrazone are related primarily to the different contributions of activation entropy in the two cases. This TSR protocol combined with other in situ kinetic methodologies including reaction progress kinetic anal. and variable time normalization anal. provides a rapid and comprehensive mechanistic picture of complex multistep catalytic reactions.

ACS Catalysis published new progress about Activation enthalpy. 401-78-5 belongs to class bromides-buliding-blocks, and the molecular formula is C7H4BrF3, HPLC of Formula: 401-78-5.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Namba, Tomoya; Hayashi, Yoshihiro; Kawauchi, Susumu; Shibata, Yu; Tanaka, Ken published the artcile< Rhodium-Catalyzed Cascade Synthesis of Benzofuranylmethylidene-Benzoxasiloles: Elucidating Reaction Mechanism and Efficient Solid-State Fluorescence>, Category: bromides-buliding-blocks, the main research area is rhodium catalysis cascade cycloisomerization bisethynylphenolsilane; benzofuranylmethylidenebenzoxasilole preparation mol modeling solid state fluorescence; fluorescence; isomerization; organosilicon compounds; rearrangement; rhodium; solid-state structures.

A new synthetic route to highly fluorescent benzofuranylmethylidenebenzoxasiloles through cationic rhodium(I)/binap complex-catalyzed cascade cycloisomerization of bis(2-ethynylphenol)silanes has been developed involving 1,2-silicon and 1,3-carbon (alkyne) migrations followed by oxycyclization. The present synthesis requires only three steps, starting from com. available dichlorodiisopropylsilane, which is markedly shorter than our previous synthesis (eight steps starting from com. available chlorodiisopropylsilane). Theor. calculations elucidated the mechanism of the above cascade cycloisomerization. This reaction is initiated by the formation of a rhodium vinylidene not through direct 1,2-silicon migration but rather through an unprecedented stepwise 1,5-silicon migration followed by C-Si bond-forming cyclization from a dearomatized allenylrhodium complex. Subsequent 1,3-carbon (alkyne) migration leading to a η3-allenyl/propargyl-rhodium complex followed by oxycyclization through π-bond (alkyne) activation with the cationic rhodium(I) complex affords the benzofuranylmethylidenebenzoxasilole product, e.g. I. The structure-fluorescence property relationships of the thus obtained benzofuranylmethylidenebenzoxasiloles were investigated, which revealed that good fluorescence quantum yields were generated in the solution state (φF=69-87 %) by introduction of electron-donating alkyl and Ph groups on two phenoxy groups. In the powder state, 4-methyl- and 4-methoxy-phenoxy derivatives exhibited efficient blue fluorescence (φF=52 % and 46 %, resp.). Especially, the 4-methylphenoxy derivative was thermally stable, and exhibited strong narrow-band fluorescence in the film state (blue, φF=95 %) and red shifted strong narrow-band fluorescence (green, φF=90 %) in the crystalline state as a result of the formation of an offset π-stacked dimer; the latter was confirmed by X-ray crystallog. anal. and by theor. calculations

Chemistry – A European Journal published new progress about Cycloisomerization. 81107-97-3 belongs to class bromides-buliding-blocks, and the molecular formula is C7H4BrF3O, Category: bromides-buliding-blocks.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Belokon’, Yuri N.; Davies, R. Gareth; Fuentes, Jose A.; North, Michael; Parsons, Teresa published the artcile< The influence of imine structure, catalyst structure and reaction conditions on the enantioselectivity of the alkylation of alanine methyl ester imines catalyzed by Cu(ch-salen)>, Application In Synthesis of 81107-97-3, the main research area is alaninate imine preparation stereoselective alkylation copper salen catalyst.

Systematic variation of the substrate structure has shown that the most effective substrates for Cu(ch-salen)-catalyzed asym. enolate alkylation reactions carried out under phase-transfer conditions are the p-chlorophenyl imines of amino esters. The other reaction parameters (solvent and stirring speed) have also been optimized. The introduction of substituents onto the aryl rings of the salen ligand was found not to have a beneficial effect on the enantioselectivity of the reaction.

Tetrahedron Letters published new progress about Alkylation catalysts. 81107-97-3 belongs to class bromides-buliding-blocks, and the molecular formula is C7H4BrF3O, Application In Synthesis of 81107-97-3.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Ravindra, Barnala; Das, Braja Gopal; Ghorai, Prasanta published the artcile< Organocatalytic, Enantioselective, Intramolecular Oxa-Michael Reaction of Alkoxyboronate: A New Strategy for Enantioenriched 1-Substituted 1,3-Dihydroisobenzofurans>, Computed Properties of 89003-95-2, the main research area is chalcone formyl pinacolborane squaramide organocatalyst reduction intramol oxa Michael; dihydroisobenzofuran stereoselective preparation.

An unprecedented strategy for the synthesis of enantioenriched 1-substituted 1,3-dihydroisobenzofurans via an enantioselective oxa-Michael reaction of o-alkoxyboronate containing chalcone has been accomplished employing cinchona alkaloid based squaramide bifunctional organocatalyst in the presence of proton source. The corresponding alkoxyboronate intermediates have been readily prepared in situ from o-formyl chalcones using neutral borane as hydride source and a tertiary amine moiety which is a counterpart of the catalyst.

Organic Letters published new progress about Aryl aldehydes Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 89003-95-2 belongs to class bromides-buliding-blocks, and the molecular formula is C8H4BrNO, Computed Properties of 89003-95-2.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Schumann, Andre; Reiss, Fabian; Jiao, Haijun; Rabeah, Jabor; Siewert, Jan-Erik; Krummenacher, Ivo; Braunschweig, Holger; Hering-Junghans, Christian published the artcile< A selective route to aryl-triphosphiranes and their titanocene-induced fragmentation>, Electric Literature of 576-83-0, the main research area is aryl triphosphirane titanocene fragmentation preparation reactivity mechanism; crystal structure mol optimized triphosphirane titanocene diphosphene preparation.

Triphosphiranes are three-membered phosphorus cycles and their fundamental reactivity has been studied in recent decades. We recently developed a high-yielding, selective synthesis for various aryl-substituted triphosphiranes. Variation of the reaction conditions in combination with theor. studies helped to rationalize the formation of these homoleptic phosphorus ring systems and highly reactive intermediates could be isolated. In addition we showed that a titanocene synthon [Cp2Ti(btmsa)] facilitates the selective conversion of these triphosphiranes into titanocene diphosphene complexes. This unexpected reactivity mode was further studied theor. and exptl. evidence is presented for the proposed reaction mechanism.

Chemical Science published new progress about Crystal structure. 576-83-0 belongs to class bromides-buliding-blocks, and the molecular formula is C9H11Br, Electric Literature of 576-83-0.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Mondragon, Alexander; Monsalvo, Ivan; Regla, Ignacio; Castillo, Ivan published the artcile< 2,4-Bis(fluorocarbon)-substituted phenols for high yield Newman-Kwart rearrangement reactions>, Synthetic Route of 81107-97-3, the main research area is thiocarbamate biphenyl trifluoromethyl preparation Newman Kwart thermal rearrangement hydrolysis; biphenylthiol trifluoromethyl preparation.

The Newman-Kwart thermal rearrangement of 2,4-disubstituted O-arylthiocarbamates I (R = Me, F3C, X = O, Z = S), prepared from the corresponding phenols, was reported. Clean conversion to the S-arylthiocarbamates I (R = Me, F3C, X = S, Z = O) in high yields was observed The rearrangement appears to be facilitated by the presence of electron-withdrawing substituents in the 2- and 4-positions of the aromatic ring.

Tetrahedron Letters published new progress about Carbamates Role: PRP (Properties), RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation) (thio). 81107-97-3 belongs to class bromides-buliding-blocks, and the molecular formula is C7H4BrF3O, Synthetic Route of 81107-97-3.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Shen, Sida; Benoy, Veronick; Bergman, Joel A.; Kalin, Jay H.; Frojuello, Mariana; Vistoli, Giulio; Haeck, Wanda; Van Den Bosch, Ludo; Kozikowski, Alan P. published the artcile< Bicyclic-Capped Histone Deacetylase 6 Inhibitors with Improved Activity in a Model of Axonal Charcot-Marie-Tooth Disease>, Product Details of C9H8BrFO2, the main research area is histone deacetylase inhibitor neuroprotectant; Charcot−Marie−Tooth disease; Selective histone deacetylase 6 inhibitor; hydroxamic acid; mitochondrial axonal transport; mutant HSPB1-expressing DRG neurons; tubulin acetylation.

Charcot-Marie-Tooth (CMT) disease is a disorder of the peripheral nervous system where progressive degeneration of motor and sensory nerves leads to motor problems and sensory loss and for which no pharmacol. treatment is available. Recently, it has been shown in a model for the axonal form of CMT that histone deacetylase 6 (HDAC6) can serve as a target for the development of a pharmacol. therapy. Therefore, the authors aimed at developing new selective and activity-specific HDAC6 inhibitors with improved biochem. properties. By utilizing a bicyclic cap as the structural scaffold from which to build upon, the authors developed several analogs that showed improved potency compared to tubastatin A while maintaining excellent selectivity compared to HDAC1. Further screening in N2a cells examining both the acetylation of α-tubulin and histones narrowed down the library of compounds to three potent and selective HDAC6 inhibitors. In mutant HSPB1-expressing DRG neurons, serving as an in vitro model for CMT2, these inhibitors were able to restore the mitochondrial axonal transport deficits. Combining structure-based development of HDAC6 inhibitors, screening in N2a cells and in a neuronal model for CMT2F, and preliminary ADMET and pharmacokinetic profiles, resulted in the selection of compound I that possesses improved biochem., functional, and druglike properties compared to tubastatin A.

ACS Chemical Neuroscience published new progress about Charcot-Marie-Tooth disease. 128577-47-9 belongs to class bromides-buliding-blocks, and the molecular formula is C9H8BrFO2, Product Details of C9H8BrFO2.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Slack, Rachel D.; Abramyan, Ara M.; Tang, Helen; Meena, Sitaram; Davis, Bruce A.; Bonifazi, Alessandro; Giancola, JoLynn B.; Deschamps, Jeffrey R.; Naing, Sett; Yano, Hideaki; Singh, Satinder K.; Newman, Amy Hauck; Shi, Lei published the artcile< A Novel Bromine-Containing Paroxetine Analogue Provides Mechanistic Clues for Binding Ambiguity at the Central Primary Binding Site of the Serotonin Transporter>, HPLC of Formula: 3893-18-3, the main research area is serotonin transporter paroxetine serotonin reuptake inhibitors SAR asym chem; Paroxetine; asymmetric chemistry; organocatalysis; selective serotonin reuptake inhibitors; serotonin transporter; structure−activity relationship.

The serotonin transporter (SERT) is the primary target for the selective serotonin reuptake inhibitors (SSRIs). However, the structural basis for the extraordinarily high binding affinity of the widely prescribed SSRI, paroxetine, to human SERT (hSERT) has not yet been fully elucidated. Our previous findings unveiled a plausible ambiguity in paroxetine’s binding orientations that may constitute an integral component of this SSRI’s high affinity for hSERT. Herein, we investigate factors contributing to paroxetine’s high affinity by modifying both the ligand and the protein. We generated a series of bromine (Br)-containing derivatives and found that the one in which the 4-F of paroxetine had been replaced with the chem. similar but more electron-rich Br atom (13) had the highest affinity. By comparatively characterizing the binding of paroxetine and 13 to both wild type (WT) and a construct harboring a paroxetine-sensitive mutation in the binding cavity, we identified a mechanistic determinant responsible for the pose ambiguity of paroxetine, which can guide future drug design.

ACS Chemical Neuroscience published new progress about Binding energy (binding affinity). 3893-18-3 belongs to class bromides-buliding-blocks, and the molecular formula is C9H7BrO, HPLC of Formula: 3893-18-3.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Zou, Wen; Liu, Xiao-Hui; Xue, Can; Zhou, Xian-Tai; Yu, Hai-Yang; Fan, Ping; Ji, Hong-Bing published the artcile< Enhancement of the visible-light absorption and charge mobility in a zinc porphyrin polymer/g-C3N4 heterojunction for promoting the oxidative coupling of amines>, Category: bromides-buliding-blocks, the main research area is zinc porphyrin microporous polymer photooxidation photocatalysis heterojunction.

Graphitic carbon nitride (g C3N4, CN) has been widely used as a photocatalyst due to its high stability and suitable band gap. However, its further development is limited due to inefficient light harvesting and rapid recombination of photogenerated carriers. In this study, a visible-light-responsive zinc porphyrin (ZnP)/CN heterojunction photocatalyst was synthesized by the combination of CN and a zinc-porphyrin-conjugated microporous polymer (ZnP-CMP). ZnP/CN exhibited excellent photocatalytic activity for the oxidative coupling of amines to imines under visible-light irradiation The efficiency of the as-developed photocatalyst was 25 times greater than that of CN and about 2 times greater than that of ZnP-CMP. The significantly enhanced catalytic efficiency was attributed to the promotion of visible-light harvesting and photogenerated charge mobility via the introduction of ZnP-CMP. The ZnP/CN heterojunction photocatalyst also exhibited excellent broad substrate scope, stability, and reusability.

Applied Catalysis, B: Environmental published new progress about Crystal vacancies (oxygen). 3959-07-7 belongs to class bromides-buliding-blocks, and the molecular formula is C7H8BrN, Category: bromides-buliding-blocks.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary

Yeh, Chien-Hung; Chen, Wei-Chen; Gandeepan, Parthasarathy; Hong, Ya-Chun; Shih, Cheng-Hung; Cheng, Chien-Hong published the artcile< RhIII-catalyzed dual directing group assisted sterically hindered C-H bond activation: a unique route to meta and ortho substituted benzofurans>, Synthetic Route of 188813-04-9, the main research area is internal alkyne hydroxyphenyloxime ether regioselective CH activation heterocyclization rhodium; benzofuran regioselective directing group assisted preparation mol crystal structure; rhodium regioselective sterically hindered CH activation heterocyclization catalyst.

A new strategy for the synthesis of highly substituted benzofurans, e.g., I (X-rays single crystal structure shown), from meta-substituted hydroxybenzenes and alkynes via a rhodium(III)-catalyzed activation of a sterically hindered C-H bond is demonstrated. A possible mechanism involving dual directing group assisted ortho C-H bond activation is proposed.

Organic & Biomolecular Chemistry published new progress about Alkynes, internal Role: RCT (Reactant), RACT (Reactant or Reagent). 188813-04-9 belongs to class bromides-buliding-blocks, and the molecular formula is C8H7BrO, Synthetic Route of 188813-04-9.

Referemce:
Bromide – Wikipedia,
bromide – Wiktionary