Electrochemical Enabled Desaturative Β-C(Sp3)-H Sulfonylation and Phosphonylation of Cyclic Amines DOI
Tao Liu, Jie Lin,

Fangjun Xia

et al.

Published: Jan. 1, 2023

Herein, we reported an efficient and straightforward desaturative β-C(sp3)-H sulfonylation phosphonylation of cyclic amines driven by electrochemistry using catalytic amounts Cp2Fe as the redox mediator. This protocol which had good functional group compatibility, provided desired enaminyl sulfone phosphine oxide products with high chemo- regio-selectivity under mild conditions. Preliminary mechanistic study indicated that underwent multiple single-electron oxidation deprotonation process, then was captured sulfonyl radical or phosphonyl to deliver products.

Language: Английский

Organic Synthesis Using Nitroxides DOI
Dirk Leifert, Armido Studer

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(16), P. 10302 - 10380

Published: Aug. 14, 2023

Nitroxides, also known as nitroxyl radicals, are long-lived or stable radicals with the general structure R1R2N–O•. The spin distribution over nitroxide N and O atoms contributes to thermodynamic stability of these radicals. presence bulky N-substituents R1 R2 prevents radical dimerization, ensuring their kinetic stability. Despite reactivity toward various transient C some nitroxides can be easily stored under air at room temperature. Furthermore, oxidized oxoammonium salts (R1R2N═O+) reduced anions (R1R2N–O–), enabling them act valuable oxidants reductants depending on oxidation state. Therefore, they exhibit interesting across all three states. Due fascinating properties, find extensive applications in diverse fields such biochemistry, medicinal chemistry, materials science, organic synthesis. This review focuses versatile For use other important fields, we will refer several articles. introductory part provides a brief overview history chemistry. Subsequently, key methods for preparing discussed, followed by an examination structural diversity physical properties. main portion this is dedicated reactions, wherein parent corresponding serve active species. It demonstrated that functional groups (such alcohols, amines, enolates, alkanes among others) efficiently oxidized. These oxidations carried out using catalysts combination stoichiometric terminal oxidants. By reducing anions, become effective reagents intriguing Nitroxides possess ability selectively react making useful terminating cascade reactions forming alkoxyamines. Depending structure, alkoxyamines weak C–O bonds, allowing thermal generation through reversible bond cleavage. Such thermally generated participate transformations, discussed end review. application strategy natural product synthesis presented.

Language: Английский

Citations

77

β-Alkenylation of Saturated N-Heterocycles via a C(sp3)–O Bond Wittig-like Olefination DOI Creative Commons

Ángel A. Nolasco-Hernández,

Leticia Quintero,

Silvano Cruz‐Gregorio

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(3), P. 1762 - 1768

Published: Jan. 12, 2024

Although the C–Hα functionalization of N-heterocycles is, in fact, an easy chemical transformation, C–Hβ on contrary, a quite difficult process. Here, we present two-step protocol that allows ready conversion pyrrolidines, piperidines, and azepane into their corresponding 3-exo-alkenyl lactams via transient formation 3-alkoxyamino followed by Wittig-like C(sp3)–O bond olefination with stabilized ylides from phosphonium salts mediated t-BuOK. Additionally, as proof synthetic effectiveness this novel methodology, first synthesis natural product callylactam A was achieved through TiCl4-catalyzed double isomerization 2-piperidone to its endo-isomer.

Language: Английский

Citations

3

Catalytic and Aerobic Oxidative C−H Annulation Reaction of Saturated Cyclic Amines for Synthesis of Dipyrroloquinolines DOI
Kenji Matsumoto,

Rina Nakano,

Ken‐ichi Yamada

et al.

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(3), P. 323 - 329

Published: Jan. 11, 2023

Abstract With the aim of providing an efficient platform for one‐step construction nitrogen‐containing polycyclic frameworks, we report a heterogeneous platinum‐catalyzed oxidative α,β‐C(sp 3 )−H dual functionalization saturated cyclic amines. This method involves tandem dehydrogenation/hetero Diels‐Alder reaction under aerobic mild conditions, tetracyclic octahydro‐dipyrroloquinoline frameworks in good yields. The was applied to synthesis natural products incargranine B aglycone and seneciobipyrrolidine one step. study provides rapid access fused compounds highly atom‐economical fashion. magnified image

Language: Английский

Citations

7

Oxidation of Alcohols to Aldehydes and Ketones using a Catalytic Pairing of a Nitroxide and Nitric Acid DOI Creative Commons
Nicholas E. Leadbeater, Manisha Sharma, Arturo León Sandoval

et al.

SynOpen, Journal Year: 2023, Volume and Issue: 07(04), P. 718 - 722

Published: Nov. 27, 2023

Abstract A methodology for the oxidation of alcohols to aldehydes and ketones is presented. The approach employs catalytic quantities a nitroxide nitric acid, with no additives or metal catalysts being required. It proves effective range aromatic, heteroaromatic, aliphatic alcohol substrates, desired products formed in good excellent yield. In case primary alcohols, can be stopped at aldehyde without concomitant formation corresponding carboxylic acid.

Language: Английский

Citations

3

Electrochemical enabled desaturated β-C(sp3)-H sulfonylation and phosphonylation of cyclic amines DOI Creative Commons
Tao Liu, Jie Lin,

Fangjun Xia

et al.

Green Synthesis and Catalysis, Journal Year: 2023, Volume and Issue: unknown

Published: Nov. 1, 2023

Herein, we reported an efficient and straightforward method to realize desaturated β-C(sp3)-H sulfonylation phosphonylation of cyclic amines driven by electrochemistry using catalytic amounts CP2Fe as the redox mediator. This protocol which had good functional group compatibility, provided desired enaminyl sulfone phosphine oxide products with high chemo- regio-selectivity under mild conditions. Several mechanistic studies have suggested that underwent multiple single-electron oxidation deprotonation processes, followed a capture step involving either sulfonyl radical or phosphonyl radical, ultimately leading products.

Language: Английский

Citations

3

Fast, easy oxidation of alcohols using an oxoammonium salt bearing the nitrate anion DOI
Arturo León Sandoval, Katrina E. Doherty, Geoffrey P. Wadey

et al.

Tetrahedron Letters, Journal Year: 2022, Volume and Issue: 116, P. 154332 - 154332

Published: Dec. 24, 2022

Language: Английский

Citations

4

Thiocarbonyl fluoride generated in situ from difluorocarbene for cyclization of vicinal X-H substituted amines (X = N, O or S) DOI

Jia-Lu Hu,

Mu-Xian Fu,

Ji‐Chang Xiao

et al.

Journal of Fluorine Chemistry, Journal Year: 2023, Volume and Issue: 272, P. 110212 - 110212

Published: Nov. 1, 2023

Language: Английский

Citations

2

Oxoammonium salt-promoted diverse functionalization of saturated cyclic amines with dinucleophiles DOI
Yan He,

Qimeng Liu,

Jintao Yang

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(26), P. 3874 - 3877

Published: Jan. 1, 2023

Oxoammonium salt-promoted diverse functionalization of saturated cyclic amines with different dinucleophiles under mild conditions is presented. Specifically, when thiocyanate used as a 1,3-dinucleophile, hexahydrothiazolo[4,5-b]pyridin-2(3H)-one derivatives are formed via the formation β-TEMPO-tethered iminium ion key intermediate. By contrast, benzene-1,2-diamine 1,4-dinucleophile, 2-alkylquinoxaline afforded generation β-oxo In addition, usefulness 2-alkylquinoxalines showcased through their facile conversion into N-(2-oxo-2-(quinoxalin-2-yl)ethyl)nitrous amides featuring synthetically useful N-NO moiety and carbonyl group.

Language: Английский

Citations

1

CBr4 as a Mild Oxidant‐Enabled Oxidation of a sp3 C−H Bond: A Facile Synthesis of the Persistent Iminium Salts of Tetrahydroisoquinolines DOI
Yuqin Chen, Shuwei Zhang, Yuemei Li

et al.

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(14)

Published: Jan. 9, 2024

Using CBr

Language: Английский

Citations

0

Direct α,β-C–H Difunctionalization of Piperidines for the Construction of the N,O-Acetal Skeleton via 1,5-Hydride Transfer DOI
Yi Zhang, Jinqiang Kuang, Yongmin Ma

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(18), P. 13373 - 13385

Published: Sept. 5, 2024

Herein, we describe an unprecedented Lewis acid-catalyzed annulation of phenols with

Language: Английский

Citations

0