Iron in Organometallic Transformations: A Sustainable Substitute for Noble Metals DOI
Rohit Kumar, Tanuja Tewari, Samir H. Chikkali

et al.

ChemCatChem, Journal Year: 2024, Volume and Issue: unknown

Published: June 6, 2024

Abstract Transition metal catalysis plays a pivotal role in chemical synthesis. Noble metals often grab significant attention organometallic due to their high reactivity. However, the serious issues associated with these such as low abundance, toxicity, geopolitical limitations, and volatile prices are driving scientific community discover sustainable alternatives. In this context, iron appears be first choice an alternative its unique properties, including range of stable oxidation states, Lewis acidity, abundance earth‘s crust, toxicity. Over past two decades, substantial progress has been made catalysis. This overview examines recent developments iron‐catalyzed industrially relevant transformations hydroformylation, olefin isomerization, hydrosilylation, hydrophosphination, carbonylation, Wacker‐type oxidation, plastic depolymerization. As witnessed throughout review, performance can significantly altered by suitable ligand selection tailoring electronic steric properties center. While noble remain industry work‐horse, is inching closer extensive understanding, it may replace near future.

Language: Английский

N2 Dissociation vs Reversible 1,2-Methyl Migration in PCNHCP Cobalt(I) Complexes in the Stereoselective Isomerization (E/Z) of Allyl Ethers DOI Creative Commons
Sakthi Raje, Subhash Garhwal, Katarzyna Młodzikowska‐Pieńko

et al.

JACS Au, Journal Year: 2024, Volume and Issue: 4(11), P. 4234 - 4248

Published: Sept. 18, 2024

With growing efforts pushing toward sustainable catalysis, using earth-abundant metals has become increasingly important. Here, we present the first examples of cobalt PC

Language: Английский

Citations

3
Iron-Catalyzed Tunable Alkene Migratory Silylation and Transposition DOI

Bohao Guo,

Yu Pu,

Ruichen Zhang

et al.

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

Published: May 8, 2025

The example of iron-catalyzed alkenes migratory silylation and transposition has been demonstrated, affording a tunable approach to synthesize thermodynamically stable allylsilanes internal with high efficiency regioselectivity. These reactions showcase several advantageous features, including good functional group tolerance, excellent regioselectivity, broad substrate scope, scalability gram-scale synthesis, late-stage functionalization bio-relevant molecules. Furthermore, the relay catalytic mechanism silylation, involving both iron-silyl iron-hydride intermediates, provides valuable insights into coupling reactions, opening new avenues for development novel transformations under iron catalysis.

Language: Английский

Citations

0
Highly efficient isomerization and hydroformylation of alkenes by rhodium supported on naturally extracted biosilica DOI
Hanuman G. Kachgunde, Murali Krishna Paidi, Sandeep Suryabhan Gholap

et al.

Materials Today Chemistry, Journal Year: 2025, Volume and Issue: 46, P. 102754 - 102754

Published: May 16, 2025

Language: Английский

Citations

0
Cathode-Induced C–H Bond Heterolysis for Olefin Isomerization and Applications in Electrocarboxylation DOI

Mengke Dong,

Shuaiqiang Jia, Xiaohong Chen

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: May 22, 2025

Olefin isomerization can not only convert terminal olefins into higher-value internal but also serve as a bridge to connect with the functionalization reaction. However, traditional methods, such base-mediated and transition-metal-mediated approaches, still face challenges like harsh conditions, low trans/cis (E/Z) ratios, unrecyclable metals, industrial scalability. Herein, we report that C-H bond could be activated at cathode form hydride ions (H-) carbon radicals, which initiate olefin via radical mechanism without base or metal catalyst assistance. Through this new mechanism, various substrates, including chemicals significant demand, effectively converted high yields, excellent E/Z scalability, all while requiring catalytic amount of electrons. Furthermore, electrochemical system was successfully applied overcome challenge electrocarboxylation nonconjugated dioxide (CO2) by isomerizing conjugated olefins. This work makes contribution chemical science for activation, opens way promising applications in isomerization-functionalization

Language: Английский

Citations

0
Enantiospecific 1,3-hydrogen transfer of alkenes and alkynes DOI
Qi Liu,

Wan-Yi Xu,

Cen-Cen You

et al.

Trends in Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 1, 2024

Language: Английский

Citations

3
Thermally Activated Geometrical Regioselective E→Z Isomerization‐Enabled Cascade Sequences of Conjugated Dienals: Experimental and DFT Studies DOI
Jayanta Saha, Soumadip Banerjee,

Sidhartha Malo

et al.

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(63)

Published: Aug. 9, 2023

The geometrical regioselective E→Z isomerization of a conjugated alkene under thermal activation pose challenge due to microscopic reversibility. Herein we report that such reversibility issues can be circumvented by integrating with subsequent cyclization cascade, particularly in the absence commonly employed light, acids, or metal-catalysts. Thus, linearly dienals mixture toluene-alcohol (2 : 1) solvents only alcohol at 60-70 °C converted γ-alkoxybutenolides moderate good yields. intermediary 2Z,4E-isomer isolated, which includes first example isolating product conditions. Density functional theory (DFT) studies have been shed light on feasibility and ensuing cascade sequences. It has observed 2E,4E→2Z,4E dienal is thermodynamically facile (ΔG <0) process. Structural elucidation further reveals presence certain charge transfer non-covalent interaction may primary reasons for enhanced stability 2Z,4E-isomer. thermodynamic plausibility reaction from Z-isomer anticipated polar protic solvent (here MeOH) also explicated. Out two probable pathways, "hemiacetal pathway" involving relay proton kinetically more feasible diminished barrier than "conjugate addition pathway".

Language: Английский

Citations

6
A Neutral PCNHCP Co(I)–Me Pincer Complex as a Catalyst for N-Allylic Isomerization with a Broad Substrate Scope DOI Creative Commons
Sakthi Raje,

Tofayel Sheikh Mohammad,

Graham de Ruiter

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(7), P. 4319 - 4325

Published: March 23, 2024

Earth-abundant-metal catalyzed double bond transposition offers a sustainable and atom-economical route toward the synthesis of internal alkenes. With an emphasis specifically on olefins ethers, isomerization allylic amines has been particularly under represented in literature. Herein, we report efficient methodology for selective N-allylic organic compounds, including amines, amides, imines. The reaction is by neutral PCNHCP cobalt(I) pincer complex proceeds via π-allyl mechanism. occurs readily at 80–90 °C, it compatible with wide variety functional groups. situ formed enamines could additionally be used one-pot inverse-electron-demand Diels–Alder to furnish series diversely substituted heterobiaryls, which further discussed this report.

Language: Английский

Citations

2
Alkene Isomerization Catalyzed by a Mn(I) Bisphosphine Borohydride Complex DOI Creative Commons
Ines Blaha, Stefan Weber,

Robin Dülger

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(17), P. 13174 - 13180

Published: Aug. 17, 2024

An additive-free manganese-catalyzed isomerization of terminal alkenes to internal is described. This reaction implementing an inexpensive nonprecious metal catalyst. The most efficient catalyst the borohydride complex cis-[Mn(dippe)(CO)2(κ2-BH4)]. operates at room temperature, with a loading 2.5 mol %. A variety effectively and selectively transformed into respective E-alkenes. Preliminary results show chain-walking elevated temperature. Mechanistic studies were carried out, including stoichiometric reactions in situ NMR analysis. These experiments are flanked by computational studies. Based on these, catalytic process initiated liberation "BH3" as THF adduct. double bond insertion M-H species, leading alkyl intermediate, followed β-hydride elimination opposite position afford product.

Language: Английский

Citations

2
Alkene Isomerization Catalyzed by a Mn(I) Bisphosphine Borohydride Complex DOI Creative Commons
Karl Kirchner, Ines Blaha,

Robin Dülger

et al.

Published: June 26, 2024

An additive-free manganese-catalyzed isomerization of terminal alkenes to internal is described. This reaction atom economic, implementing an inexpensive, non-precious metal catalyst. The most efficient catalyst the borohydride complex cis-[Mn(dippe)(CO)2(κ2-BH4)]. operates at room temperature with a loading 2.5 mol %. A variety are effectively and selectively transformed respective E-alkenes. Preliminary results show chain walking elevated temperature. Mechanistic studies were carried out including stochiometric reactions in situ NMR analysis. These experiments flanked by computational studies. Based on these, catalytic process initiated liberation “BH3” as hydroborated alkene. double bond insertion into M–H species leading alkyl intermediate, followed β-hydride elimination opposite position afford product.

Language: Английский

Citations

1
A Hydride Migration Mechanism for the Mo‐Catalyzed Z‐2‐Selective Isomerization of Terminal Alkenes DOI Creative Commons

Sarah E. Jenny,

Juan M. I. Serviano, Ainara Nova

et al.

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(23)

Published: Oct. 19, 2023

Abstract The catalytic one‐bond isomerization (transposition) of 1‐alkenes is an emerging approach to Z ‐2‐alkenes. Design more selective catalysts would benefit from a mechanistic understanding factors controlling selectivity. We propose here reaction pathway for cis ‐Mo(CO) 4 (PCy 3 )(piperidine) ( ), precatalyst that shows high selectivity transposition alpha olefins (e. g., 1‐octene 2‐octene, 18 : 1 E at 74 % conversion). Computational modeling pathways and isotopic labeling suggests the takes place via allyl (1,3‐hydride shift) pathway, where oxidative addition fac ‐(CO) Mo(PCy )(η 2 ‐alkene) followed by hydride migration one position C carbon) another hydride/CO exchanges. Calculated barriers are lower than explored alternative mechanisms change hapticity, rotation). To our knowledge, this first study such in alkene isomerization.

Language: Английский

Citations

3