Cobalt(iii)-catalyzed weakly coordinating arylurea-directed regioselective mono-olefination DOI

Shuo‐Jie Shen,

Zhen Zhang,

Yi Gu

et al.

Organic & Biomolecular Chemistry, Journal Year: 2022, Volume and Issue: 21(2), P. 300 - 305

Published: Dec. 1, 2022

Here, we developed an air-stable, earth-abundant cobalt(III)-catalyzed regioselective mono-olefination of arenes directed by urea under mild conditions through a cross-dehydrogenative coupling (CDC) process. Under the optimized conditions, high regioselectivity was achieved with various electron-rich and electron-deficient arenes, which afforded E-alkenylated products (with yields up to 90%). In contrast used for noble-metal-catalyzed olefination weakly coordinating groups, our reaction operated including temperature (40 °C) non-metallic oxidant.

Language: Английский

Transition‐Metal‐Catalyzed, Chelation‐Assisted C−H Alkenylation and Allylation of Organic Molecules with Unactivated Alkenes DOI

Ravichandran Logeswaran,

Masilamani Jeganmohan

Advanced Synthesis & Catalysis, Journal Year: 2022, Volume and Issue: 364(13), P. 2113 - 2139

Published: May 6, 2022

Abstract Olefins are important building blocks and widely utilized in synthetic organic chemistry. Owing to its omnipresence unique reactivity, the functionalization of alkenes has become a powerful method for constructing complex molecules. In this context, direct chelation‐assisted C−H olefination at inert bonds represents most straightforward introducing alkenyl group into compounds highly regio‐ stereoselective manner. Despite remarkable advances reaction, successful transformations restricted activated or electronically biased olefins such as acrylates, styrenes, acrylamides, vinyl sulfones, phosphonates. Literature reports on with unactivated unbiased limited due poor intrinsic reactivity regioselectivity issues. significant challenges, past few years have witnessed tremendous growth. The present review describes recent allylation aromatics, alkenes, heteroaromatics via concerted‐metallation‐ deprotonation pathway.Transition metals palladium, rhodium, iridium cobalt used these kind transformations. scope, mechanistic investigation, limitation alkenylation reactions discussed elaborately. includes all reported base‐assisted pathway. magnified image

Language: Английский

Citations

31
Synthesis of CF3-Substituted N-Heterocyclic Compounds Based on C–H Activation-Initiated Formal [2 + 3] Annulation Featuring with a Latent Nucleophilic Site DOI

Manqing Wang,

Shengnan Yan,

Bin Li

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(11), P. 7828 - 7842

Published: May 22, 2024

Presented herein is a novel synthesis of CF

Language: Английский

Citations

6
Cobalt(II)-Catalyzed Selective C2–H Heck Reaction of Native (N–H) Indoles Enabled by Salicylaldehyde Ligand DOI
Jia‐Wei Li, Shuai Shi, Xiaohong Chen

et al.

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

Published: Jan. 8, 2025

Direct functionalization of native (N–H) indoles via C–H activation remains a challenge. Herein, we report salicylaldehyde-promoted cobalt-catalyzed selective C2–H Heck reaction with both active and unactivated olefins in the presence free N–H bonds. A series structurally diverse C2-alkenylated including natural product drug derivatives were prepared directly effectively without additional preprotection deprotection procedures.

Language: Английский

Citations

0
Oxidative Alkenylation of (Hetero)aromatics with Unactivated Alkenes: Control of the Reaction Selectivity DOI
Chenhui Hu, Keyu Xiang, Ying Tao

et al.

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(9), P. 1922 - 1949

Published: Feb. 23, 2024

Abstract Alkenylbenzene skeletons represent one of the most widely occurring structural motifs in pharmaceutical drugs, natural products, and advanced materials. The construction alkenylbenzenes is promising through use a straightforward oxidative alkenylation protocol, particularly from unactivated alkenes. This significant because alkenes are inexpensive raw materials that can be obtained bulk quantities petrochemical feedstocks renewable resources. However, controlling reactivity regioselectivity olefination with unbiased olefins remains challenge, necessitating continuous efforts potentially having substantial impact on both organic synthesis industry. review aims to provide an overview latest advances regiocontrol strategies for reactions alkenes, which categorized into three types: 1) ligand‐promoted/accelerated reactions; 2) prefunctionalized olefins‐facilitated 3) directing group‐induced reactions.

Language: Английский

Citations

3
Chiral Transient Ligand Enabled Enantioselective Synthesis of Atropisomers Decorated with Unactivated Olefins via a Palladium-Catalyzed C–H Olefination DOI

Vadivel Arjun,

Masilamani Jeganmohan

Organic Letters, Journal Year: 2023, Volume and Issue: 25(42), P. 7606 - 7611

Published: Oct. 16, 2023

Herein, atroposelective synthesis of axially chiral biaryls with unactivated olefins by a palladium-catalyzed C-H olefination using transient directing group strategy has been disclosed. This protocol is well compatible variety biaryl-2-aldehydes as various such allyl sulfonamides and sulfones to provide the olefinated products in synthetically useful yields excellent enantioselectivities up >99% ee. In addition, wide number biaryl alcohols were synthesized simple diversification enantioselectivity.

Language: Английский

Citations

8
Condition‐Controlled Divergent Synthesis of Imidazoindolone Spiroisoquinolinones fromN‐Alkoxycarboxamide Indoles and Diazo Homophthalimides DOI

Manqing Wang,

Qianting Zhou,

Xinying Zhang

et al.

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(8), P. 1255 - 1261

Published: March 24, 2023

Abstract Presented herein is a condition‐controlled divergent synthesis of imidazoindolone spiro‐isoquinolinones (IISIQs) via the cascade reactions N ‐alkoxycarboxamide indoles with diazo homophthalimides. When reaction carried out under air and in absence an acid additive, IISIQ tethered ‐alkoxy moiety (IISIQ‐OR) formed through Rh(III)‐catalyzed C−H/N−H metalation, carbene formation/ migratory insertion followed by reductive elimination, which acts as oxidant to regenerate Rh(III) catalyst. run argon presence MesCO 2 H, on other hand, IISIQ−H rhodacycle intermediate formation, acid‐assisted intramolecular substitution/annulation N−O bond cleavge. In general, this method provides approach toward spiroheterocyclic scaffolds features accessible substrates, functional group compatibility external oxidant. Moreover, value developed protocol further showcased gram‐scale structural transformation products. magnified image

Language: Английский

Citations

7
Rh(III)-Catalyzed Enone Carbonyl/Ketone-Directed Aerobic C–H Olefination of Aromatics with Unactivated Olefins DOI

Chikkabagilu Nagaraju Shambhavi,

Masilamani Jeganmohan

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(19), P. 13236 - 13258

Published: Sept. 21, 2022

A Rh(III)-catalyzed weak enone carbonyl/ketone-assisted aerobic oxidative C–H olefination of aromatics with unactivated alkenes has been developed. This protocol involves cross-dehydrogenative Heck-type reaction various substituted biologically relevant chalcones and aromatic ketones such as acetophenones chromones functionalized olefins in moderate to good yields. Further, ortho-alkylation norbornene is also demonstrated. possible mechanism involving chelation-assisted activation/insertion/β-hydride elimination was proposed supported by the deuterium labeling studies.

Language: Английский

Citations

10
Copper-catalyzed [3+2] annulation of O-acyl ketoximes with 2-aryl malonates for the synthesis of 3-aryl-4-pyrrolin-2-ones DOI

Xiaoqing Song,

Xiao-Qi Qiang,

Zi-Jun Hu

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(35), P. 5225 - 5228

Published: Jan. 1, 2023

A copper-catalyzed [3+2] annulation of O -acyl ketoximes with 2-aryl malonates for the concise synthesis 3-aryl-4-pyrrolin-2-ones has been developed.

Language: Английский

Citations

5
Rh(iii)-catalyzed redox-neutral C–H alkenylation of benzamides with gem-difluorohomoallylic silyl ethers via β-H elimination DOI

Xueli Cui,

Jing Qu,

Jianfeng Yi

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(25), P. 3747 - 3750

Published: Jan. 1, 2023

Fluorinated molecules are widely used in pharmaceutical and agrochemical industries. Herein we report the synthesis of 2-(3,3-difluoro-4-(silyloxy)but-1-en-1-yl)benzamides from unprecedented rhodium(III)-catalyzed alkenylation various benzamides with difluorohomoallylic silyl ethers. The practicability this protocol is demonstrated by its broad substrate compatibility, good functional group tolerance, ready scalability high regioselectivity. oxygen ethers makes β-H elimination feasible, which suppresses both β-F dialkenylation benzamides. This redox-neutral reaction proceeds efficiently via N-O bond cleavage without external oxidants thus provides new opportunities for elaborate difluorinated compounds readily available fluorinated synthons.

Language: Английский

Citations

2
Isatoic anhydride as a masked directing group and internal oxidant for Rh(III)-catalyzed decarbonylative annulation through C–H activation: insights from DFT calculations DOI
Yanshu Luo, Maosheng Zhang, Yuanzhi Xia

et al.

Chemical Communications, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

DFT calculations uncovered that the isatoic anhydride is a masked directing group and internal oxidant for Rh( iii )-catalyzed decarbonylative annulation through C–H activation.

Language: Английский

Citations

0