Tag: M.W=250-300

Zhang, Chun; Santiago, Celine B.; Kou, Lei; Sigman, Matthew S. published the artcile< Alkenyl Carbonyl Derivatives in Enantioselective Redox Relay Heck Reactions: Accessing α,β-Unsaturated Systems>, Formula: C13H15F3N2O, the main research area is arylboronic acid unsaturated carbonyl enantioselective regioselective arylation Heck; aryl unsaturated carbonyl stereoselective preparation.

A highly enantioselective and site-selective Pd-catalyzed arylation of alkenes linked to carbonyl derivatives to yield α,β-unsaturated systems is reported. The high site selectivity is attributed to both a solvent effect and the polarized nature of the carbonyl group, both of which have been analyzed through multidimensional anal. tools. The reaction can be performed in an iterative fashion allowing for a diastereoselective installation of two aryl groups along an alkyl chain.

Journal of the American Chemical Society published new progress about Arylation, stereoselective (regioselective). 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Formula: C13H15F3N2O.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Mei, Tian-Sheng; Patel, Harshkumar H.; Sigman, Matthew S. published the artcile< Enantioselective construction of remote quaternary stereocentres>, Name: (R)-4-(tert-Butyl)-2-(5-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole, the main research area is trisubstituted alkenyl alc arylboronic acid palladium relay Heck arylation; aryl carbonyl compound quaternary carbon substituted stereoselective preparation.

Small mols. that contain all-carbon quaternary stereocenters-carbon atoms bonded to four distinct carbon substituents-are found in many secondary metabolites and some pharmaceutical agents. The construction of such compounds in an enantioselective fashion remains a long-standing challenge to synthetic organic chemists. In particular, methods for synthesizing quaternary stereocenters that are remote from other functional groups are underdeveloped. Here we report a catalytic and enantioselective intermol. Heck-type reaction of trisubstituted-alkenyl alcs. with aryl boronic acids. This method provides direct access to quaternary all-carbon-substituted β-, γ-, δ-, ε- or ζ-aryl carbonyl compounds, because the unsaturation of the alkene is relayed to the alc., resulting in the formation of a carbonyl group. The scope of the process also includes incorporation of pre-existing stereocenters along the alkyl chain, which links the alkene and the alc., in which the stereocenter is preserved. The method described allows access to diverse mol. building blocks containing an enantiomerically enriched quaternary center.

Nature (London, United Kingdom) published new progress about Alkenyl alcohols Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 1428537-19-2 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Name: (R)-4-(tert-Butyl)-2-(5-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Xu, Liping; Hilton, Margaret J.; Zhang, Xinhao; Norrby, Per-Ola; Wu, Yun-Dong; Sigman, Matthew S.; Wiest, Olaf published the artcile< Mechanism, Reactivity, and Selectivity in Palladium-Catalyzed Redox-Relay Heck Arylations of Alkenyl Alcohols>, Recommanded Product: (S)-4-(tert-Butyl)-2-(5-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole, the main research area is palladium catalyzed redox relay Heck arylation alkenyl alc mechanism.

The enantioselective Pd-catalyzed redox-relay Heck arylation of acyclic alkenyl alcs. allows access to various useful chiral building blocks from simple olefinic substrates. Mechanistically, after the initial migratory insertion, a succession of β-hydride elimination and migratory insertion steps yields a saturated carbonyl product instead of the more general Heck product, an unsaturated alc. Here, we investigate the reaction mechanism, including the relay function, yielding the final carbonyl group transformation. M06 calculations predict a ΔΔG# of 1 kcal/mol for the site selectivity and 2.5 kcal/mol for the enantioselectivity, in quant. agreement with exptl. results. The site selectivity is controlled by a remote electronic effect, where the developing polarization of the alkene in the migratory insertion transition state is stabilized by the C-O dipole of the alc. moiety. The enantioselectivity is controlled by steric repulsion between the oxazoline substituent and the alc.-bearing alkene substituent. The relay efficiency is due to an unusually smooth potential energy surface without high barriers, where the hydroxyalkyl-palladium species acts as a thermodn. sink, driving the reaction toward the carbonyl product. Computational predictions of the relative reactivity and selectivity of the double bond isomers are validated exptl.

Journal of the American Chemical Society published new progress about Alkenyl alcohols Role: PEP (Physical, Engineering or Chemical Process), PRP (Properties), RCT (Reactant), PROC (Process), RACT (Reactant or Reagent). 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Recommanded Product: (S)-4-(tert-Butyl)-2-(5-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Chen, Guihua; Cao, Jian; Wang, Qian; Zhu, Jieping published the artcile< Desymmetrization of Prochiral Cyclopentenes Enabled by Enantioselective Palladium-Catalyzed Oxidative Heck Reaction>, Formula: C13H15F3N2O, the main research area is desymmetrization cyclopentene enantioselective oxidative Heck palladium catalyst; oxidative Heck arylboronic acid cyclopentene palladium catalyst diastereoselective enantioselective.

In the presence of a catalytic amount of Pd(TFA)2 and a chiral Pyox ligand under oxygen atm., oxidative Heck reaction between arylboronic acids and 4-substituted or 4,4-disubstituted cyclopent-1-enes afforded the chiral arylated products with concurrent creation of two stereocenters in good yields with excellent diastereo- and enantioselectivities.

Organic Letters published new progress about Arylboronic acids Role: RCT (Reactant), RACT (Reactant or Reagent). 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Formula: C13H15F3N2O.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

McCammant, Matthew S.; Sigman, Matthew S. published the artcile< Development and investigation of a site selective palladium-catalyzed 1,4-difunctionalization of isoprene using pyridine-oxazoline ligands>, Category: pyridine-derivatives, the main research area is pyridine oxazoline ligand preparation; polyene regioselective diastereoselective preparation; isoprene vinyl triflate vinylboronic acid palladium catalyst difunctionalization.

Palladium-catalyzed 1,4-difunctionalizations of isoprene that produce skipped polyenes were reported. Complex isomeric product mixtures were possible as a result of the difficult-to-control migratory insertion of isoprene into a Pd-alkenyl bond, but good site selectivity was achieved using easily accessible pyrox ligands. Mechanistic studies suggest that the control of insertion was the result of the unique electronic asymmetry and steric properties of the ligand.

Chemical Science published new progress about Addition reaction catalysts, stereoselective (regioselective). 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Category: pyridine-derivatives.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Allen, Jamie R.; Bahamonde, Ana; Furukawa, Yukino; Sigman, Matthew S. published the artcile< Enantioselective N-Alkylation of Indoles via an Intermolecular Aza-Wacker-Type Reaction>, SDS of cas: 1428537-19-2, the main research area is indolylalkanal chemoselective enantioselective preparation; chemoselective enantioselective aza Wacker reaction allylic homoallylic alc indole; enantioselective alkylation indole allylic homoallylic alc palladium catalyst; stereochem mechanism aza Wacker reaction deuterated allylic alc indole.

In the presence of Pd(MeCN)2(OTs)2 and a nonracemic pyridinyloxazoline, 3-substituted indoles such as 3-phenylindole underwent intermol., chemoselective, and enantioselective alkylation/aza-Wacker reactions with cis-allylic and cis-homoallylic alcs. such as (Z)-EtCH:CHCH2OH mediated by p-benzoquinone in 1,2-dichloroethane to yield nonracemic β- and γ-(1-indolyl)alkanals such as I; enamines generated under other conditions were not formed. The mechanism was studied using the reaction of a deuterium-labeled allylic alc.; the stereochem. of the product supported a syn amino-palladation mechanism for the reaction.

Journal of the American Chemical Society published new progress about Alcohols, homoallylic Role: RCT (Reactant), RACT (Reactant or Reagent). 1428537-19-2 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, SDS of cas: 1428537-19-2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Dang, Yanfeng; Qu, Shuanglin; Wang, Zhi-Xiang; Wang, Xiaotai published the artcile< A Computational Mechanistic Study of an Unprecedented Heck-Type Relay Reaction: Insight into the Origins of Regio- and Enantioselectivities>, Related Products of 1416819-91-4, the main research area is Heck type relay reaction mechanism regioselectivity enantioselectivity.

D. functional theory (DFT) calculations (B3LYP and M06) have been utilized to study a newly reported Heck-type reaction that uses an allylic or alkenyl alc. as substrate and palladium as catalyst in the form of a chelate with a chiral pyridine oxazoline (PyrOx) ligand. The reaction not only controls the regio- and enantioselectivities of arylation of the C=C bond, but also forms the carbonyl functionality up to four bonds away from the aryl substituent via tandem C=C bond migration and enol-to-keto conversion. Computations performed on representative reaction systems allow us to propose a detailed mechanism with several key steps. Initial oxidation of palladium(0) by aryldiazonium generates active arylpalladium(II) species that bind the C=C bond of an allylic or alkenyl alc. The activated C=C bond inserts into the palladium-aryl moiety to attain aryl substitution and a chiral carbon center, and the resulting complex undergoes β-hydride elimination to give a new C=C bond that can repeat the insertion/elimination process to move down the carbon chain to form an enol that tautomerizes to a highly stable carbonyl final product. The calculations reveal that the C=C bond migratory insertion step determines both the regioselectivity and the enantioselectivity of arylation, with the former arising mainly from the electronic effect of the hydroxyl group on the charge distribution over the C=C bond and the latter originating from a combination of steric repulsion, trans influence, and C-H/π dispersion interactions.

Journal of the American Chemical Society published new progress about Alkenyl alcohols Role: PEP (Physical, Engineering or Chemical Process), PRP (Properties), RCT (Reactant), PROC (Process), RACT (Reactant or Reagent). 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Related Products of 1416819-91-4.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Nakamura, Hugh; Yasui, Kosuke; Kanda, Yuzuru; Baran, Phil S. published the artcile< 11-Step Total Synthesis of Teleocidins B-1-B-4>, Category: pyridine-derivatives, the main research area is teleocidin B synthesis.

A unified and modular approach to the teleocidin B family of natural products is presented that proceeds in 11 steps and features an array of interesting strategies and methods. Indolactam V, the known biosynthetic precursor to this family, was accessed through electrochem. amination, Cu-mediated aziridine opening, and a remarkable base-induced macrolactamization. Guided by a desire to minimize concession steps, the tactical combination of C-H borylation and a Sigman-Heck transform enabled the convergent, stereocontrolled synthesis of the teleocidins.

Journal of the American Chemical Society published new progress about Amination (electrochem.). 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Category: pyridine-derivatives.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ma, Teng; Chen, Yate; Li, Yuxiu; Ping, Yuanyuan; Kong, Wangqing published the artcile< Nickel-Catalyzed Enantioselective Reductive Aryl Fluoroalkenylation of Alkenes>, Recommanded Product: (R)-4-(tert-Butyl)-2-(5-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole, the main research area is nickel catalyzed enantioselective reductive aryl monofluoroalkenylation alkene; aryl bromide gem difluoroalkene monofluoroalkenylation; oxindole monofluoroalkenyl substituent preparation.

Enantioselective Ni-catalyzed reductive aryl monofluoroalkenylation of alkenes between aryl bromides and gem-difluoroalkenes has been developed. The reaction proceeding under room temperature and base-free reaction conditions tolerates a wide range of functional groups on both coupling partners. Various synthetically useful oxindoles containing monofluoroalkenyl substituent are obtained in good yields with 85%-95% enantiomeric excess. In addition, the synthetic method can be further applied to the late-stage monofluoroalkenylation of complex biol. active compounds

ACS Catalysis published new progress about Alkenylation (monofluoro-). 1428537-19-2 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Recommanded Product: (R)-4-(tert-Butyl)-2-(5-(trifluoromethyl)pyridin-2-yl)-4,5-dihydrooxazole.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Patel, Harshkumar H.; Sigman, Matthew S. published the artcile< Palladium-Catalyzed Enantioselective Heck Alkenylation of Acyclic Alkenols Using a Redox-Relay Strategy>, Product Details of C13H15F3N2O, the main research area is alkenyl triflate alkenol acyclic palladium Heck alkenylation catalyst; aldehyde acyclic stereoselective preparation.

We report a highly enantioselective intermol. Heck reaction of alkenyl triflates and acyclic primary or racemic secondary alkenols. The mild reaction conditions permit installation of a wide range of alkenyl groups at positions β, γ, or δ to a carbonyl group in high enantioselectivity. The success of this reaction is attributed to the use of electron-withdrawing alkenyl triflates, which offer selective β-hydride elimination followed by migration of the catalyst through the alkyl chain to give the alkenylated carbonyl products. The synthetic utility of the process is demonstrated by a two-step modification of a reaction product to yield a tricyclic core structure, present in various natural products.

Journal of the American Chemical Society published new progress about Aliphatic aldehydes Role: SPN (Synthetic Preparation), PREP (Preparation). 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Product Details of C13H15F3N2O.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem