Category: 210169-54-3

Kalkman, Eric D.; Hartwig, John F. published an article in 2021. The article was titled 《Direct Observation of Diastereomeric α-C-Bound Enolates during Enantioselective α-Arylations: Synthesis, Characterization, and Reactivity of Arylpalladium Fluorooxindole Complexes》, and you may find the article in Journal of the American Chemical Society.Reference of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole The information in the text is summarized as follows:

The Pd-catalyzed asym. α-arylation of carbonyl compounds is a valuable strategy to form benzylic stereocenters. However, the origin of the stereoselectivity of these reactions is poorly understood, and little is known about the reactivity of the putative diastereomeric arylpalladium enolate intermediates. To this end, the authors report the synthesis and characterization of diphosphine-ligated arylpalladium fluoroenolate complexes, including complexes bearing a metal-bound, stereogenic C and an enantioenriched chiral diphosphine ligand. These complexes reductively eliminate to form chiral α-aryl-α-fluorooxindoles with enantioselectivities and rates that are relevant to those of the catalytic process with SEGPHOS as the ancillary ligand. Kinetic studies showed that the rate of reductive elimination is slightly slower than the rate of epimerization of the intermediate, causing the reductive elimination step to impart the greatest influence on the enantioselectivity. DFT calculations of these processes are consistent with these exptl. rates and suggest that the minor diastereomer forms the major enantiomer of the product. The rates of reductive elimination from complexes containing a variety of electronically varied aryl ligands revealed the unusual trend that complexes bearing more electron-rich aryl ligands react faster than those bearing more electron-poor aryl ligands. Noncovalent Interaction (NCI) and Natural Bond Orbital (NBO) analyses of the transition-state structures for reductive elimination from the SEGPHOS-ligated complexes revealed key donor-acceptor interactions between the Pd center and the fluoroenolate fragment. These interactions stabilize the pathway to the major product enantiomer more strongly than they stabilize that to the minor enantiomer. The results came from multiple reactions, including the reaction of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Reference of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) may be used for: rhodium-catalyzed asymmetric formal olefination or cycloaddition of 1,3-dicarbonyl compounds with 1,6-diynes or 1,6-enynes, stereoselective preparation of homoallylic alcohols via Ir-catalyzed stereoselective transfer hydrogenative crotylation of an allylic acetate with alcohols or aldehydesReference of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

SDS of cas: 210169-54-3In 2016 ,《Hydroxymethylation beyond Carbonylation: Enantioselective Iridium-Catalyzed Reductive Coupling of Formaldehyde with Allylic Acetates via Enantiotopic π-Facial Discrimination》 appeared in Journal of the American Chemical Society. The author of the article were Garza, Victoria J.; Krische, Michael J.. The article conveys some information:

Chiral iridium complexes modified by SEGPHOS catalyze the 2-propanol-mediated reductive coupling of branched allylic acetates with formaldehyde to form primary homoallylic alcs. with excellent control of regio- and enantioselectivity. These processes, which rely on enantiotopic π-facial discrimination of σ-allyliridium intermediates, represent the first examples of enantioselective formaldehyde C-C coupling beyond aldol addition The experimental part of the paper was very detailed, including the reaction process of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3SDS of cas: 210169-54-3)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) is a chelating ligand used to prepare coordination complex catalysts, such as its use in Pd catalysts for the enantioselective synthesis of spiro- or benzofused hetereocycles with exocyclic olefins via enantioselective intramolecular dearomative Heck reaction of indoles, benzofurans, pyrroles and furans.SDS of cas: 210169-54-3

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

In 2019,Bulletin of the Chemical Society of Japan included an article by Tsukamoto, Hirokazu; Kawase, Ayumu; Omura, Hirotaka; Doi, Takayuki. Application of 210169-54-3. The article was titled 《Key Factors for High Diastereo- and Enantioselectivity of Umpolung Cyclizations of Aldehyde-Containing Allylpalladium Intermediates》. The information in the text is summarized as follows:

Two palladium/chiral diphosphine-catalyzed umpolung cyclizations of aldehyde-containing allylic acetates and allenes with arylboronic acid are fully investigated to establish key factors in their high stereoselectivities. Both cyclization reactions afford cis-disubstituted pyrrolidine and THF. These occur in high diastereo- and enantioselectivities through a common cationic (Z)-η1-allylpalladium, toward which a ring strain generated in the cyclization step leading to trans-isomers biases the equilibrium through η3-η1-η3-complex in the former cyclization. Varied diastereoselectivities were observed in the formation of five-membered carbocycles and six-membered heterocycles. These reflect release of a ring strain generated in the cyclization step leading to trans-isomers and a different distribution of the (Z)- and the (E)-η1-allylpalladium intermediates generated by the oxidative addition of allylic acetates to Pd(0) or carbopalladation of allenes, resp. A sterically demanding substituent at the center of the allyl moiety is necessary for high diastereo- and enantioselectivity. The enantioselectivity of the former cyclization was lowered by the presence of organometallic reductants or reagents, possibly causing the formation of neutral η1-allylpalladium species. We used a chiral allylic acetate containing (E)-deuterium-labeled alkene to demonstrate that the electrophilic attack of the aldehyde to the allyl ligand occurred on the side where the palladium existed, consistent with the Zimmerman-Traxler transition state. In the experiment, the researchers used (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Application of 210169-54-3)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) may be used for: regio- and stereoselective preparation of axially chiral arylnaphthalene derivatives via rhodium-catalyzed [2+2+2] cycloaddition of diynes with naphthalenepropynoic acid derivatives or diastereo- and enantioselective hydrogenation of α-amino-β-keto ester hydrochlorides catalyzed by an iridium complex.Application of 210169-54-3

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

《Enantioselective total synthesis of furofuran lignans via Pd-catalyzed asymmetric allylic cycloaddition of vinylethylene carbonates with 2-nitroacrylates》 was written by Zhao, Can; Khan, Ijaz; Zhang, Yong Jian. Recommanded Product: (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2020. The article conveys some information:

Herein, a practical and efficient approach to tetrahydrofurans with three-stereocenters has been developed through Pd-catalyzed asym. allylic cycloaddition of vinylethylene carbonates (VECs) with 2-nitroacrylates under mild conditions. By using this asym. catalytic reaction as a key step, several furofuran lignans with stereodivergency have been effectively synthesized through 5- or 6-step sequences from readily available starting materials. The experimental part of the paper was very detailed, including the reaction process of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Recommanded Product: (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) may be used for: rhodium-catalyzed asymmetric formal olefination or cycloaddition of 1,3-dicarbonyl compounds with 1,6-diynes or 1,6-enynes, stereoselective preparation of homoallylic alcohols via Ir-catalyzed stereoselective transfer hydrogenative crotylation of an allylic acetate with alcohols or aldehydesRecommanded Product: (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis