Regiocontrolled Halogen Dance and In Situ Transmetalation of Pyrroles Directed by the α-Substituent DOI
Kentaro Okano,

Daichi Matsuyama,

Tatsuki Okumi

et al.

Synlett, Journal Year: 2023, Volume and Issue: 35(16), P. 1919 - 1923

Published: Dec. 28, 2023

Abstract Multiply substituted pyrroles are found in medicines, natural products, and functional materials. A general method for introducing functionality on the pyrrole ring is thus required. Herein, a regiocontrolled halogen dance reaction an situ transmetalation of α-functionalized bromopyrroles reported. Selective generation isomeric pyrrolylmetal species was achieved by using ethyl ester or phenyl group at α-position switching between transmetalation. These reactions proceeded smoothly when N,N-dimethylsulfamoyl attached to nitrogen atom, providing corresponding products 68% quantitative yields 1-mmol scale. This applicable formal synthesis Kendine 91.

Language: Английский

Ultrafast Halogen Dance Reactions of Bromoarenes Enabled by Catalytic Potassium Hexamethyldisilazide DOI
Kengo Inoue, Atsunori Mori, Kentaro Okano

et al.

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(23)

Published: Feb. 8, 2024

Abstract Lochmann–Schlosser base, a stoichiometric combination of n BuLi and KO t Bu, is commonly used as superbase for deprotonating wide range organic compounds. In the present study, we report that catalytic potassium hexamethyldisilazide (KHMDS) exhibits higher activity than Bu successive bromine–metal exchanges. Accordingly, 1–10 mol% KHMDS dramatically enhances halogen dance reactions to introduce various electrophiles bromopyridine, bromoimidazole, bromothiophene, bromofuran, bromobenzene derivatives with bromo group translocated from original position. A dual cycle proposed explain ultrafast bromine transfer.

Language: Английский

Citations

3
Catalytic Approaches to the Halogen Dance Reaction for Molecular Editing DOI
Kengo Inoue, Kentaro Okano

ChemCatChem, Journal Year: 2024, Volume and Issue: 16(14)

Published: March 30, 2024

Abstract Transposition reactions, i. e., switching the position of functional groups, are a powerful tool for molecular editing. The transposition halogen atom attached to an aromatic ring, referred as dance reaction, has great potential in fields pharmaceuticals, agrochemicals, natural products, and materials. However, substrate scope this reaction is limited owing intrinsic difficulty facilitating multiple catalytic cycles involving several aryllithium species. In concept paper, recent advances catalysis that have expanded highlighted.

Language: Английский

Citations

3
Ultrafast Halogen Dance Reactions Enabled by Catalytic Potassium Hexamethyldisilazide DOI Creative Commons
Kengo Inoue, Atsunori Mori, Kentaro Okano

et al.

Published: Jan. 2, 2024

Lochmann–Schlosser base, a stoichiometric combination of nBuLi and KOtBu, is commonly used as superbase for deprotonating wide range organic compounds. In the present study, we report that catalytic potassium hexamethyldisilazide (KHMDS) exhibits higher activity than KOtBu successive bromine–metal exchanges. Accordingly, 1–10 mol% KHMDS dramatically enhances halogen dance reactions to introduce various electrophiles bromopyridine, bromoimidazole, bromothiophene, bromofuran, bromobenzene derivatives with bromo group translocated from original position. A dual cycle proposed explain ultrafast bromine transfer.

Language: Английский

Citations

1
Catalytic Activity of Triphenylphosphine for Electrophilic Aromatic Bromination Using N-Bromosuccinimide and Process Safety Evaluation DOI
Masahiro Hosoya, Kenichi Ishibashi,

Takafumi Ohara

et al.

Organic Process Research & Development, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 2, 2024

Language: Английский

Citations

1
Ultra-Fast Halogen Dance Enabled by Catalytic KHMDS DOI Creative Commons
Kengo Inoue, Atsunori Mori, Kentaro Okano

et al.

Published: Nov. 16, 2023

Catalytic potassium hexamethyldisilazide (KHMDS) accelerates a bromine–metal exchange rather than tert-butoxide (KOtBu), which is stoichiometrically used for the Lochmann–Schlosser base, combination of nBuLi and KOtBu. Loading 1.0–10 mol% KHMDS drastically facilitated successive exchanges consisting halogen dance reaction within 1 min to introduce various electrophiles on bromopyridine, imidazole, thiophene, furan, benzene derivatives with bromo group translocated from original position. A dual catalytic cycle proposed explain ultra-fast bromine transfer showing significant potential realize new reactions aryllithium species using KHMDS.

Language: Английский

Citations

1
C1 Functionalization of β-Carboline via Knochel–Hauser Base-Directed Metalation and Negishi Coupling DOI
Jin Tan, Kyle Clagg, Haiming Zhang

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 14, 2024

The synthesis of C1-functionalized β-carbolines from

Language: Английский

Citations

0
Regiocontrolled Halogen Dance and In Situ Transmetalation of Pyrroles Directed by the α-Substituent DOI
Kentaro Okano,

Daichi Matsuyama,

Tatsuki Okumi

et al.

Synlett, Journal Year: 2023, Volume and Issue: 35(16), P. 1919 - 1923

Published: Dec. 28, 2023

Abstract Multiply substituted pyrroles are found in medicines, natural products, and functional materials. A general method for introducing functionality on the pyrrole ring is thus required. Herein, a regiocontrolled halogen dance reaction an situ transmetalation of α-functionalized bromopyrroles reported. Selective generation isomeric pyrrolylmetal species was achieved by using ethyl ester or phenyl group at α-position switching between transmetalation. These reactions proceeded smoothly when N,N-dimethylsulfamoyl attached to nitrogen atom, providing corresponding products 68% quantitative yields 1-mmol scale. This applicable formal synthesis Kendine 91.

Language: Английский

Citations

0