Transformable Transient Directing Group-Assisted C(sp2)–H Activation: Synthesis and Late-Stage Functionalizations of o-Alkenylanilines DOI
Bubul Das, Anjali Dahiya, Ashish Kumar Sahoo

et al.

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(19), P. 13383 - 13388

Published: Sept. 14, 2022

The isocyanate group in aryl isocyanates serves as a transformable transient directing Ru(II)-catalyzed ortho olefination leading to o-alkenylanilines. In alcoholic solvents, are transformed into carbamates, which initiate the insertion of acrylates via o-C-H activation. particular, tAmOH dual role solvent-cum mediator. o-alkenylanilines converted azacoumarins and subsequently C-4 aryl-substituted using iodides coupling partners Pd(II)-catalyzed C-H functionalizations.

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

33
Looking deep into C–H functionalization: the synthesis and application of cyclopentadienyl and related metal catalysts DOI
Guilherme A. M. Jardim, Renato L. Carvalho, Mateus P. Nunes

et al.

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(19), P. 3101 - 3121

Published: Jan. 1, 2022

This feature review is focused on recent key applications of commonly used transition-metal Cp-type catalysts for C–H bond functionalizations.

Language: Английский

Citations

23
Recent advances in rhodium-catalysed cross-dehydrogenative-coupling between two C(sp2)–H bonds DOI

Yi Ling Tsang,

Pui Ying Choy, Man Pan Leung

et al.

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(7), P. 1992 - 2012

Published: Jan. 1, 2022

A comprehensive review overviewing the advances in Rh-catalyzed cross-dehydrogenative-coupling period of 2016–2021 is presented.

Language: Английский

Citations

21
Scandium-Catalyzed Benzylic C(sp3)–H Alkenylation of Tertiary Anilines with Alkynes DOI
Xian Xu,

Qianlin Sun,

Xin Xu

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(22), P. 3970 - 3975

Published: May 31, 2022

This work describes the chemo- and stereoselective benzylic C(sp3)-H alkenylation of tertiary ortho-methyl anilines with internal alkynes using a simple β-diketiminato scandium catalyst. protocol offers an efficient method for synthesis new family ortho-allylanilines in high yields. The resultant products facilely underwent further chemical transformation to other valuable anilines. A cationic benzyl species was isolated from stoichiometric reaction confirmed be catalytic intermediate.

Language: Английский

Citations

14
Synthesis of allylanilines via scandium-catalysed benzylic C(sp3)–H alkenylation with alkynes DOI
Wei Zhou, Xuefeng Cong, Masayoshi Nishiura

et al.

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(52), P. 7257 - 7260

Published: Jan. 1, 2022

The ortho-selective benzylic C(sp3)-H alkenylation of 2-methyl tertiary anilines with internal alkynes has been achieved for the first time by using a half-sandwich scandium catalyst. This protocol provides straightforward route synthesis new family 2-allylaniline derivatives, featuring broad substrate scope, 100% atom-efficiency, high yields, and chemo-, regio-, stereoselectivity.

Language: Английский

Citations

11
DFT Study on Mechanism of Ni–Al Bimetallic-Catalyzed C–H Cyclization to Construct Tricyclic Imidazoles: Roles of NHC Ligand and AlMe3 DOI
Cong Zhang, Guorong Li,

Zhenfeng Shang

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(3), P. 1505 - 1514

Published: Jan. 13, 2024

The mechanism of the Ni–Al bimetallic-catalyzed C–H cyclization to construct tricyclic imidazoles is investigated using density functional theory calculations. calculation result shows that reaction involves sequential steps substrate coordination, ligand-to-ligand hydrogen transfer (LLHT), and C–C reductive elimination produce final product imidazole. LLHT step calculated be rate-determining step. oxidative addition benzimidazole bond Ni center insertion alkene into Ni–H occur concertedly in effects N-heterocyclic carbene (NHC) ligands AlMe3 on reactivity regioselectivity were also analyzed. These results shed light some ambiguous suggestions from experiments.

Language: Английский

Citations

1
Asymmetric synthesis of cyclopenta[b]indoles via organocatalytic formal (3 + 2) cyclization of β-keto ester with azonaphthalene DOI

Yanji Song,

Shi Tang,

Qianping Chen

et al.

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(11), P. 2734 - 2739

Published: Jan. 1, 2023

Enantioselective formal (3 + 2) cyclization of cyclic β-keto esters with azonaphthalenes to synthesize cyclopenta[ b ]indoles in good yields high diastereo- and enantioselectivity is established by using guanidine-amides as catalysts under mild reaction conditions.

Language: Английский

Citations

3
Ni(ii)-catalyzed C–H hydroarylation of diarylacetylenes with imidazolium salts DOI
Tianbao Wang, Xuesong Zheng,

Qinze Zheng

et al.

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(16), P. 2730 - 2733

Published: Jan. 1, 2022

A simple Ni(II)-catalyzed C-H hydroarylation of diarylacetylenes with imidazolium salts without adding any ligand was developed. It provides a facile and efficient access to (E)-2-(1,2-diarylvinyl)imidazolium salts. The preliminary results indicate rare nonredox catalytic cycle Ni(II), complementary the common redox starting from Ni(0).

Language: Английский

Citations

3
Transformable Transient Directing Group-Assisted C(sp2)–H Activation: Synthesis and Late-Stage Functionalizations of o-Alkenylanilines DOI
Bubul Das, Anjali Dahiya, Ashish Kumar Sahoo

et al.

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(19), P. 13383 - 13388

Published: Sept. 14, 2022

The isocyanate group in aryl isocyanates serves as a transformable transient directing Ru(II)-catalyzed ortho olefination leading to o-alkenylanilines. In alcoholic solvents, are transformed into carbamates, which initiate the insertion of acrylates via o-C-H activation. particular, tAmOH dual role solvent-cum mediator. o-alkenylanilines converted azacoumarins and subsequently C-4 aryl-substituted using iodides coupling partners Pd(II)-catalyzed C-H functionalizations.

Language: Английский

Citations

3