Dual Photoredox and Copper Catalysis: Enantioselective 1,2-Amidocyanation of 1,3-Dienes

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(11), P. 7523 - 7528

Published: May 19, 2023

Dual photoredox–transition-metal catalysis has emerged as a powerful tool for the development of chemical transformations. However, its application in selective difunctionalization 1,3-dienes remains essentially unexploited. By synergistic action photoredox and copper catalysts, we report herein an enantioselective 1,2-amidocyanation 1,3-dienes. Visible-light irradiation chloroform solution conjugated dienes, N-Boc-amidopyridinium salts, TMSCN presence catalytic amount fac-Ir(ppy)3, Cu(OTf)2·xH2O, chiral Box ligand affords three-component adducts good to high yields with regio- enantioselectivities. A L*CuCN complex, fully characterized spectroscopically confirmed by X-ray crystallographic analysis, is able catalyze transformation, therefore supporting inner-sphere cyanide transfer pathway.

Language: Английский

---

Palladium(0) π-Lewis Base Catalysis: Concept and Development

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(10), P. 6422 - 6437

Published: March 1, 2024

The development of a new catalytic strategy plays vital role in modern organic chemistry since it permits bond formation an unprecedented and more efficient manner. Although the application preformed metal complexes as π-base-activated reagents have enabled diverse transformations elegantly, concept by directly utilizing transition metals π-Lewis base catalysts remain underdeveloped, especially field asymmetric catalysis. Here, we outline our perspective on discovery palladium(0) catalyst, which is capable increasing highest occupied molecular orbital (HOMO) energy both electron-neutral electron-deficient 1,3-dienes 1,3-enynes upon flexible η2-complexes formed situ resultant π-backdonation. Thus, fruitful carbon–carbon-forming reactions with electrophiles can be achieved enantioselectively vinylogous addition pattern, conceptually different from classical oxidative cyclization mechanism. Emphasis will given to mechanism elucidation, features, reaction design together further this emerging field.

Language: Английский

---

Rhodium‐Catalyzed Asymmetric Hydrogenation and Transfer Hydrogenation of 1,3‐Dipolar Nitrones

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(14)

Published: Feb. 17, 2024

Abstract Owing to their distinctive 1,3‐dipolar structure, the catalytic asymmetric hydrogenation of nitrones hydroxylamines has been a formidable and longstanding challenge, characterized by intricate enantiocontrol susceptibility N−O bond cleavage. In this study, transfer were accomplished with tethered TsDPEN‐derived cyclopentadienyl rhodium(III) catalyst (TsDPEN: p ‐toluenesulfonyl‐1,2‐diphenylethylene‐1,2‐diamine), reaction proceeds via novel 7‐membered cyclic transition state, producing chiral up 99 % yield >99 ee. The practical viability methodology was underscored gram‐scale reactions subsequent transformations. Furthermore, mechanistic investigations DFT calculations also conducted elucidate origin enantioselectivity.

Language: Английский

---

Cobalt‐Catalyzed Enantioselective Alkenylation of Aldehydes

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(33)

Published: May 31, 2024

Catalytic enantioselective alkenylation of aldehydes with easily accessible alkenyl halides promoted by a chiral cobalt complex derived from newly developed tridentate bisoxazolinephosphine is presented. Such processes represent an unprecedented reaction pathway for catalysis and general approach that enable rapid construction highly diversified enantioenriched allylic alcohols containing 1,1-, 1,2-disubstituted trisubstituted alkene as well axial stereogenicity in up to 99 % yield : 1 er without the need preformation alkenyl-metal reagents. DFT calculations revealed origin enantioselectivity.

Language: Английский

---

Enantioselective Synthesis of Hydrindanes via Palladium-Catalyzed Asymmetric Desymmetrization of Cyclohexadiene Derivatives

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 5, 2025

We herein disclose a strategy for the asymmetric desymmetrization of cyclohexadiene derivatives via palladium-catalyzed Heck and tandem Heck/Tsuji-Trost allylic alkoxylation reaction. By employing DCE as solvent, we obtained variety chiral hydrindanes containing an all-carbon quaternary carbon center tertiary in good yields with excellent enantioselectivities. With alcohols valuable one stereocenter two centers were constructed high level enantioinduction.

Language: Английский

---

Enantioselective and stereodivergent hydromonofluoroalkylation of conjugated and remote dienes

Chinese Chemical Letters, Journal Year: 2023, Volume and Issue: 34(12), P. 108371 - 108371

Published: March 23, 2023

Language: Английский

---

Palladium-Catalyzed Asymmetric Hydrofunctionalizations of Conjugated Dienes

Chinese Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 43(8), P. 2614 - 2614

Published: Jan. 1, 2023

Because of the broad substrate availability, high atom economy and efficient stereocontrol, palladium-catalzyed asymmetric hydrofunctionalizations conjugated dienes have emerged as an route to construct enantioenriched allylic motifs, including C-C, C-N, C-S, C-P, C-Si C-O bonds.The development, advance mechanistic features this area in past decades are summarized.Based on types stereogenic centers constructed via strategy, review is divided into six parts, hydroalkylation, hydroamination, hydrophosphinylation, hydrosulfonylation, hydrosilylation hydroalkoxylation.

Language: Английский

---

Ligand‐Dictated Regiodivergent Allylic Functionalizations via Palladium‐Catalyzed Remote Substitution

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(28)

Published: March 15, 2023

Different from classical allylic substitutions that require a vicinal leaving group, an olefin bearing remote group is scarcely viewed as potential allylation substrate. Herein, we describe feasible protocols to achieve regiodivergent C-H functionalizations via palladium-catalyzed substitution, which provides novel strategy for the seldomly studied migratory Tsuji-Trost reaction. Dictated by suitable ligand, process involved 4,3-hydrofunctionalization of generated conjugated diene intermediate metal walking observed in generally >20 : 1 regioselectivity. Unexpectedly, related 1,4-hydrofunctionalization pathway found be major route with newly synthesized electron-rich bisphosphine challenges conventional viewpoint on regioselectivity hydrofunctionalizations linear internal dienes η3 -substitution. A series deuterium experiments and kinetic studies provide preliminary insight into catalytic cycle.

Language: Английский

---

Enantioselective Palladium‐Catalyzed Directed Migratory Allylation of Remote Dienes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(34)

Published: June 30, 2023

Chain walking has been an efficient route to realize the functionalization of inert C(sp3 )-H bonds, but this strategy is limited mono-olefin migration and functionalization. Herein, we demonstrate feasibility tandem directed simultaneous migrations remote olefins stereoselective allylation for first time. The adoption palladium hydride catalysis secondary amine morpholine as solvent critical achieving high substrate compatibility stereochemical control with method. protocol also applicable three vicinal bonds thus construct continuous stereocenters along a propylidene moiety via short synthetic process. Preliminary mechanistic experiments corroborated design dienes.

Language: Английский

---

Synthesis of Sterically Hindered Dialkyl Ethers via Palladium-Catalyzed Fluoro-alkoxylation of gem-Difluoroalkenes

Organic Letters, Journal Year: 2024, Volume and Issue: 26(23), P. 4953 - 4957

Published: May 30, 2024

Organofluorine compounds are of high value in medicinal and agricultural chemistry. Herein, we report a palladium-catalyzed fluoro-alkoxylation gem-difluoroalkenes for the synthesis much more challenging sterically hindered ethers. This reaction represents direct method α-trifluoromethyl ethers with broad functional group tolerance excellent regioselectivity. system employs N-fluorobenzenesulfonimide (NFSI) as an electrophilic fluorine source alcohols nucleophilic donors, including but not limited to tert-substituted alcohols.

Language: Английский

---