Palladium‐Catalyzed 2‐Aminoacetophenone Oxime Directed β‐sp2 and γ‐sp3 C─H Bond Functionalization of Aryl Carboxamides DOI
Rathinam Sankar, Gnanasambandam Vasuki

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(45)

Published: Nov. 26, 2024

Abstract Pd(II)‐catalyzed 2‐aminoacetophenone oxime‐assisted sp 2 and 3 C─H arylation of aryl carboxamides is disclosed. The oxime an N,N ‐bidentate auxiliary that proceeds activation through a six‐membered palladacycle intermediate, the activation/functionalization on C(sp )─H bond by ligand novel achieved. This facilitates subsequent in one step. optimized protocol enables access to various groups at β ‐sp ‐ γ ‐centers carboxamides. bidentate easy synthesize gram scale, we also described deoximination procedure after functionalization.

Language: Английский

Synthesis of Polyfunctional Indazoles via Novel Rearrangement of Isatin Derivatives DOI Open Access
Elena N. Bezsonova, В. А. Тафеенко, S. E. Sosonyuk

et al.

Asian Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 3, 2025

Abstract In this work we present a new method for indazole synthesis through the unexpected rearrangement of various 7‐nitroisatins during reaction with hydrazine hydrate. The pyrazole cycle is formed via direct metal‐free C−H amination. We demonstrate limitations discovered approach and several accessible methods functionalization compounds to obtain novel derivatives.

Language: Английский

Citations

0
Regioselective Aryne Annulations of N-Tosyl-2-enamides and N-tert-Butylsulfinyl-2-enamides for the Construction of Dihydroquinolin-4-one and Chroman-4-imine Units DOI
Aimin Zhang,

Suh Young Yu,

Jihye Lee

et al.

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

Published: Feb. 14, 2025

A regioselective synthesis of the dihydroquinolin-4-one 4 is achieved from aryne-mediated annulation an o-(trimethylsilyl)aryl triflate 1 with N-tosyl-2-enamide 2 in presence TBAT toluene, whereas chroman-4-imine 5 formed reaction N-(tert-butylsulfinyl)-2-enamide 3 and TBAF THF. Governing factors for regioselectivity have been accounted as strong steric electronic effects between N-toluenesulfonyl N-tert-butylsulfinyl groups 3. The methods described herein are successful various substrates or high levels regioselectivity, diastereoselectivity 5.

Language: Английский

Citations

0
Cobalt‐Promoted Para C─H Amination of 3‐Acetyl Substituted Nitroarenes with Arylhydrazines DOI

Duyen K. Nguyen,

Giang Binh Tran, Tung T. Nguyen

et al.

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(43)

Published: Nov. 1, 2024

Abstract We report a method to furnish substituted 1H ‐indazoles via coupling of 3‐acetyl nitroarenes and arylhydrazines. Reactions progressed in the presence cobalt(II) acetylacetonate catalyst, TEMPO oxidant, Cs 2 CO 3 base. Functional groups including bromo, chloro, nitro, trifluoromethoxy were compatible with reaction conditions. The proposed mechanism was based on nucleophilic substitution hydrogen para nitro group. Our feature convenient pathway directly obtain which avoid use pre‐functionalized starting materials. Indazole could play role as directing group for palladium‐catalyzed C(sp )─H arylation iodobenzene.

Language: Английский

Citations

1
Hydroxylamine‐O‐Sulfonic Acid (HOSA): A Recent Synthetic Overview DOI

Puneet Kumar,

Ashirwad Divedi,

Dinesh Chandra

et al.

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(35)

Published: Sept. 12, 2024

Abstract Hydroxylamine‐ O‐ sulfonic acid has been used as a versatile nitrogen source in synthetic organic chemistry. It dual function and utilized both nucleophile an electrophile during different transformations. This reagent is stable easy to handle aqueous solvents. can be with functional groups under mild reaction conditions, making its widely applicable for constructing complex molecules. various applications such agrochemicals, pharmaceuticals, polymer industries the formation of S−N, C−N, O−N, N−N bonds, well efficient cyclization reactions metal‐free conditions excellent stereo– regioselectivity. The present review provides brief overview all advancements made past two decades using hydroxylamine‐ source.

Language: Английский

Citations

0
Palladium‐Catalyzed 2‐Aminoacetophenone Oxime Directed β‐sp2 and γ‐sp3 C─H Bond Functionalization of Aryl Carboxamides DOI
Rathinam Sankar, Gnanasambandam Vasuki

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(45)

Published: Nov. 26, 2024

Abstract Pd(II)‐catalyzed 2‐aminoacetophenone oxime‐assisted sp 2 and 3 C─H arylation of aryl carboxamides is disclosed. The oxime an N,N ‐bidentate auxiliary that proceeds activation through a six‐membered palladacycle intermediate, the activation/functionalization on C(sp )─H bond by ligand novel achieved. This facilitates subsequent in one step. optimized protocol enables access to various groups at β ‐sp ‐ γ ‐centers carboxamides. bidentate easy synthesize gram scale, we also described deoximination procedure after functionalization.

Language: Английский

Citations

0