Mechanistic Investigation of Zirconium-Catalyzed Hydroaminoalkylation of Alkynes: Substrate and Ligand Effects DOI
Erick Nuñez Bahena, Sofia A. Sirohey, Laurel L. Schafer

et al.

Organometallics, Journal Year: 2023, Volume and Issue: 42(12), P. 1291 - 1299

Published: March 8, 2023

The mechanism of zirconium-catalyzed hydroaminoalkylation diphenylacetylene, and the origin contrasting reactivity with N-benzylaniline or N-(trimethylsilyl)benzylamine substrates, have been investigated. Isolated intermediates revealed that nature C–H activation C–C bond-forming steps in alkyne are analogous to those alkene variant, regardless amine substrate. In alkynes, open coordination sphere at zirconium center, supported by bis(ureate) ligand, enables neutral protic donors. This is essential for promoting catalytic turnover these reactions. Under conditions, dimethylamine acts as a proton source releasing allylic products while minimizing formation side products. Additionally, we identified homoleptic tetra(ureate) complex main catalyst decomposition pathway hydroaminoalkylation. similar structures further favored when employing smaller bis(urea) proligands, thus explaining poor performance some ligands catalysis. However, increasing proligand size minimize such favors isomerization side-products resulting reduced yields desired product. study provides ligand design principles guide development coordinatively flexible catalysts achieve systems rely upon protonolysis steps,

Language: Английский

Hydroformylation of pyrolysis oils to aldehydes and alcohols from polyolefin waste DOI
Houqian Li, Jiayang Wu, Zhen Jiang

et al.

Science, Journal Year: 2023, Volume and Issue: 381(6658), P. 660 - 666

Published: Aug. 10, 2023

Waste plastics are an abundant feedstock for the production of renewable chemicals. Pyrolysis waste produces pyrolysis oils with high concentrations olefins (>50 weight %). The traditional petrochemical industry uses several energy-intensive steps to produce from fossil feedstocks such as naphtha, natural gas, and crude oil. In this work, we demonstrate that oil can be used aldehydes through hydroformylation, taking advantage olefin functionality. These then reduced mono- dialcohols, oxidized dicarboxylic acids, or aminated diamines by using homogeneous heterogeneous catalysis. This route high-value oxygenated chemicals low-value postconsumer recycled polyethylene. We project produced could lower greenhouse gas emissions ~60% compared their petroleum feedstocks.

Language: Английский

Citations

81
Anti-Markovnikov Intermolecular Hydroamination of Alkenes and Alkynes: A Mechanistic View DOI Creative Commons
Jorge Escorihuela, Agustı́ Lledós, Gregori Ujaque

et al.

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(15), P. 9139 - 9203

Published: July 5, 2023

Hydroamination, the addition of an N–H bond across a C–C multiple bond, is reaction with great synthetic potential. Important advances have been made in last decades concerning catalysis these reactions. However, controlling regioselectivity amine toward formation anti-Markovnikov products (addition to less substituted carbon) still remains challenge, particularly intermolecular hydroaminations alkenes and alkynes. The goal this review collect systems which hydroamination terminal alkynes has achieved. focus will be placed on mechanistic aspects such reactions, discern step at decided unravel factors that favor regioselectivity. In processes entailing direct alternative pathways, involving several reactions accomplish (formal processes), also discussed review. catalysts gathered embrace most metal groups Periodic Table. Finally, section discussing radical-mediated metal-free approaches, as well heterogeneous catalyzed processes, included.

Language: Английский

Citations

59
Cobalt-catalyzed synthesis of amides from alkenes and amines promoted by light DOI
Mason S. Faculak, Alexander M. Veatch, Erik J. Alexanian

et al.

Science, Journal Year: 2024, Volume and Issue: 383(6678), P. 77 - 81

Published: Jan. 4, 2024

Catalytic methods to couple alkene and amine feedstocks are valuable in synthetic chemistry. The direct carbonylative coupling of alkenes amines holds promise as a perfectly atom-economical approach amide synthesis, but general remain underdeveloped. Herein, we report an hydroaminocarbonylation catalyzed by unmodified, inexpensive cobalt carbonyl under mild conditions low pressure promoted light. Silane addition after the reaction enables sequential cobalt-catalyzed reduction, constituting formal hydroaminomethylation. These exhibit exceptional scope across both components with high chemo- regioselectivity proceed efficiently even absence solvent. formation hydridocobalt through photodissociation ligand is proposed enable catalytic activity conditions, which addresses long-standing challenge catalysis.

Language: Английский

Citations

24
An unprecedented 2-fold interpenetrated open framework built from Zn6 ring seamed trivacant polyoxotungstates used for photocatalytic synthesis of pyridine derivatives DOI
Xianqiang Huang, Sen Liu, Gang Liu

et al.

Applied Catalysis B Environment and Energy, Journal Year: 2022, Volume and Issue: 323, P. 122134 - 122134

Published: Nov. 1, 2022

Language: Английский

Citations

62
Remote and Proximal Hydroaminoalkylation of Alkenes Enabled by Photoredox/Nickel Dual Catalysis DOI

Songlin Zheng,

Wenlong Wang, Weiming Yuan

et al.

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(39), P. 17776 - 17782

Published: Sept. 22, 2022

A mild and site-selective hydroaminoalkylation of activated unactivated alkenes via dual photoredox/Ni catalysis is developed. This catalytic strategy enables exclusive access to α-selective products, which complementary previously reported photocatalytic that provides the β-selective products. The chain-walking a Ni–H intermediate toward carbonyl allows for at remote sp3 C–H sites. method tolerates broad substrate scope both amines as well providing streamlined synthesis value-added β-amino acid derivatives from readily available starting materials.

Language: Английский

Citations

55
Nickel/Photoredox Dual-Catalyzed Regiodivergent Aminoalkylation of Unactivated Alkyl Halides DOI
Wenlong Wang, Xueyuan Yan, Ye Fu

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(42), P. 23385 - 23394

Published: Oct. 12, 2023

A mild and regiodivergent aminoalkylation of unactivated alkyl halides is disclosed via a dual photoredox/nickel catalysis. Bipyridyl-type ligands without an ortho-substituent control the site-selective coupling at original position, while ortho-disubstituted tune site-selectivity remote, unprefunctionalized position. Mechanistic studies combined with DFT calculations give insight into mechanism origins ligand-controlled regioselectivity. Notably, this redox-neutral, alkyl-alkyl features conditions, broad substrate scope for both partners, excellent offers straightforward way α-alkylation tertiary amines to synthesize structurally diverse alkylamines value-added amino acid derivatives.

Language: Английский

Citations

30
Ligand-Controlled Regiodivergent Nickel-Catalyzed Hydroaminoalkylation of Unactivated Alkenes DOI
Tianze Zhang, Shan Jiang,

Mengying Qian

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(5), P. 3458 - 3470

Published: Jan. 25, 2024

Ligand modulation of transition-metal catalysts to achieve optimal reactivity and selectivity in alkene hydrofunctionalization is a fundamental challenge synthetic organic chemistry. Hydroaminoalkylation, an atom-economical approach for alkylating amines using alkenes, particularly significant amine synthesis the pharmaceutical, agrochemical, fine chemical industries. However, existing methods usually require specific substrate combinations precise regio- stereoselectivity, which limits their practical utility. Protocols allowing regiodivergent hydroaminoalkylation from same starting materials, controlling both regiochemical stereochemical outcomes, are currently absent. Herein, we report ligand-controlled, nickel-catalyzed unactivated alkenes with

Language: Английский

Citations

9
Organocatalytic radical relay trifunctionalization of unactivated alkenes by a combination of cyano migration and alkylacylation DOI
Jingyi Wang, Yuchan Wang, Jibin Li

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(36), P. 5395 - 5398

Published: Jan. 1, 2023

The first N-heterocyclic carbene organocatalytic three-component radical relay trifunctionalization of unactivated alkenes through the combination remote 1,4-cyano migration and alkylacylation was reported. This protocol features mild reaction conditions, readily available materials, excellent regioselectivity, capability late-stage functionalization.

Language: Английский

Citations

21
Iridium‐Catalyzed Remote Site‐Switchable Hydroarylation of Alkenes Controlled by Ligands DOI
Fei Li, Yicong Luo,

Jinbao Ren

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(41)

Published: Aug. 23, 2023

An iridium-catalyzed remote site-switchable hydroarylation of alkenes was reported, delivering the products functionalized at subterminal methylene and terminal methyl positions on an alkyl chain controlled by two different ligands, respectively, in good yields with to excellent site-selectivities. The catalytic system showed functional group tolerance a broad substrate scope, including unactivated activated alkenes. More importantly, regioconvergent transformations mixtures isomeric were also successfully realized. results mechanistic studies demonstrate that reaction undergoes chain-walking process give [Ar-Ir-H] complex alkene. subsequent processes proceed through modified Chalk-Harrod-type mechanism via migratory insertion alkene into Ir-C bond followed C-H reductive elimination afford hydrofunctionalization site-selectively.

Language: Английский

Citations

14
The Effect of Basic Ligands and Alkenes on the Regioselectivity of C−H Additions of Tertiary Amines to Alkenes DOI
Da Li, Yuji Wang, Shiyu Wang

et al.

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(32)

Published: April 4, 2024

Abstract Highly regioselective C−H alkylation reactions of tertiary anilines and alkyl amines with simple alkenes have been achieved by the use imidazolin‐2‐iminato scandium complexes. This protocol provided an efficient atom‐economical route to structurally diverse amine derivatives. The basic ligand, a coordinating THF in catalyst substitution alkene substrates were found switch regioselectivity presumably due generation different types catalytically active species or formation relatively stable intermediates. On basis deuterium labeling experiments KIE experiments, possible catalytical cycles understand reaction mechanism as well regioselectivity.

Language: Английский

Citations

6