molecules-logo

Journal Browser

Journal Browser

Ligands in Catalysis

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Organometallic Chemistry".

Deadline for manuscript submissions: closed (31 December 2021) | Viewed by 16842

Special Issue Editor


E-Mail Website
Guest Editor
Department of Chemistry, Rutgers University, 73 Warren St, Newark, NJ 07102, USA
Interests: amide bonds; N-heterocyclic carbenes; Pd-NHCs; C–N activation; C–H activation; C–O activation; amide bond activation; ester activation; cross-coupling; catalysis; decarbonylative couplings; Suzuki–Miyaura; reductions; lanthanides; reductive couplings; radical chemistry; synthetic methodology; natural products
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Ligand design occupies a central place in organic synthesis and catalysis. The ability of ligands to engender a variety of useful properties of organometallic complexes is the major enabling force for the discovery of new catalytic reactions, activation of small molecules, dramatically enhanced reactivity, exquisite chemo-, regio- and enantioselectivity, practical and user-friendly properties of organometallic complexes, stabilization of reactive organometallic species or unusual oxidation and bonding states of elements. Prominent examples include the discovery of bulky, electron-rich phosphine and NHC ligands that have revolutionized Pd-catalyzed cross-couplings, imidazolidinylidene ligands in olefin metathesis or chiral phosphines in asymmetric hydrogenation. These transformations are now critically important in academic and industrial research and a part of the everyday toolbox of all chemists. More recent developments have focused on the development of ligands for sustainable first-row transition metals, early transition metals, f-block elements, ambiphilic ligands or redox-active ligands, including in the very important area of photoredox catalysis and cooperation between two metal centers in multimetallic catalysis. It is clear that future advancements in metal complexes and their applications crucially depend on ligand design, whereas the ligand electronic, steric and topological properties provide numerous improvements to the reactivity and selectivity at the metal centers. This Special Issue aims to provide a broad survey of recent advances in ligand design in organometallic chemistry and outline various approaches in the field.

The Organometallic Section highlights important facets of organometallic chemistry on the interface of organic and inorganic chemistry, covering organometallic chemistry aspects ranging from synthesis to application. For more details, see:

https://www.mdpi.com/journal/molecules/sections/organometallic_chemistry

Prof. Dr. Michal Szostak
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Molecules is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • ligands
  • catalysis
  • organometallic chemistry
  • ligand design
  • metal chemistry
  • transition metals
  • main group metals
  • f-block metals
  • phosphines
  • phosphine ligands
  • NHCs
  • N-heterocyclic carbenes
  • Pd-NHCs
  • bipyridine ligands
  • biaryl phosphines
  • pincer complexes
  • bidentate ligands
  • s-donors
  • electron-deficient ligands
  • cooperating ligands
  • non-innocent ligands
  • transition-metal complexes
  • homogeneous catalysis
  • cross-coupling
  • hydrogenation
  • bond activation
  • redox-active ligands
  • ambiphilic ligands
  • ancillary ligands
  • photoredox catalysis
  • asymmetric catalysis
  • lanthanides

Published Papers (5 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

13 pages, 2827 KiB  
Article
Electrocatalytic CO2 Reduction and H2 Evolution by a Copper (II) Complex with Redox-Active Ligand
by Jingjing Li, Shifu Zhang, Jinmiao Wang, Xiaomeng Yin, Zhenxing Han, Guobo Chen, Dongmei Zhang and Mei Wang
Molecules 2022, 27(4), 1399; https://doi.org/10.3390/molecules27041399 - 18 Feb 2022
Cited by 6 | Viewed by 1972
Abstract
The process of electrocatalytic CO2 reduction and H2 evolution from water, regarding renewable energy, has become one of the global solutions to problems related to energy consumption and environmental degradation. In order to promote the electrocatalytic reactivity, the study of the [...] Read more.
The process of electrocatalytic CO2 reduction and H2 evolution from water, regarding renewable energy, has become one of the global solutions to problems related to energy consumption and environmental degradation. In order to promote the electrocatalytic reactivity, the study of the role of ligands in catalysis has attracted more and more attention. Herein, we have developed a copper (II) complex with redox-active ligand [Cu(L1)2NO3]NO3 (1, L1 = 2-(6-methoxypyridin-2-yl)-6-nitro-1h-benzo [D] imidazole). X-ray crystallography reveals that the Cu ion in cation of complex 1 is coordinated by two redox ligands L1 and one labile nitrate ligand, which could assist the metal center for catalysis. The longer Cu-O bond between the metal center and the labile nitrate ligand would break to provide an open coordination site for the binding of the substrate during the catalytic process. The electrocatalytic investigation combined with DFT calculations demonstrate that the copper (II) complex could homogeneously catalyze CO2 reduction towards CO and H2 evolution, and this could occur with great performance due to the cooperative effect between the central Cu (II) ion and the redox- active ligand L1. Further, we discovered that the added proton source H2O and TsOH·H2O (p-Toluenesulfonic acid) could greatly enhance its electrocatalytic activity for CO2 reduction and H2 evolution, respectively. Full article
(This article belongs to the Special Issue Ligands in Catalysis)
Show Figures

Graphical abstract

15 pages, 12940 KiB  
Article
Iron-Catalyzed Cross-Coupling Reactions of Alkyl Grignards with Aryl Chlorobenzenesulfonates
by Elwira Bisz
Molecules 2021, 26(19), 5895; https://doi.org/10.3390/molecules26195895 - 29 Sep 2021
Cited by 3 | Viewed by 2424
Abstract
Aryl sulfonate esters are versatile synthetic intermediates in organic chemistry as well as attractive architectures due to their bioactive properties. Herein, we report the synthesis of alkyl-substituted benzenesulfonate esters by iron-catalyzed C(sp2)–C(sp3) cross-coupling of Grignard reagents with aryl chlorides. [...] Read more.
Aryl sulfonate esters are versatile synthetic intermediates in organic chemistry as well as attractive architectures due to their bioactive properties. Herein, we report the synthesis of alkyl-substituted benzenesulfonate esters by iron-catalyzed C(sp2)–C(sp3) cross-coupling of Grignard reagents with aryl chlorides. The method operates using an environmentally benign and sustainable iron catalytic system, employing benign urea ligands. A broad range of chlorobenzenesulfonates as well as challenging alkyl organometallics containing β-hydrogens are compatible with these conditions, affording alkylated products in high to excellent yields. The study reveals that aryl sulfonate esters are the most reactive activating groups for iron-catalyzed alkylative C(sp2)–C(sp3) cross-coupling of aryl chlorides with Grignard reagents. Full article
(This article belongs to the Special Issue Ligands in Catalysis)
Show Figures

Figure 1

9 pages, 2241 KiB  
Communication
Self-Assembled Bimetallic Aluminum-Salen Catalyst for the Cyclic Carbonates Synthesis
by Wooyong Seong, Hyungwoo Hahm, Seyong Kim, Jongwoo Park, Khalil A. Abboud and Sukwon Hong
Molecules 2021, 26(13), 4097; https://doi.org/10.3390/molecules26134097 - 5 Jul 2021
Cited by 4 | Viewed by 3050
Abstract
Bimetallic bis-urea functionalized salen-aluminum catalysts have been developed for cyclic carbonate synthesis from epoxides and CO2. The urea moiety provides a bimetallic scaffold through hydrogen bonding, which expedites the cyclic carbonate formation reaction under mild reaction conditions. The turnover frequency (TOF) [...] Read more.
Bimetallic bis-urea functionalized salen-aluminum catalysts have been developed for cyclic carbonate synthesis from epoxides and CO2. The urea moiety provides a bimetallic scaffold through hydrogen bonding, which expedites the cyclic carbonate formation reaction under mild reaction conditions. The turnover frequency (TOF) of the bis-urea salen Al catalyst is three times higher than that of a μ-oxo-bridged catalyst, and 13 times higher than that of a monomeric salen aluminum catalyst. The bimetallic reaction pathway is suggested based on urea additive studies and kinetic studies. Additionally, the X-ray crystal structure of a bis-urea salen Ni complex supports the self-assembly of the bis-urea salen metal complex through hydrogen bonding. Full article
(This article belongs to the Special Issue Ligands in Catalysis)
Show Figures

Figure 1

13 pages, 2635 KiB  
Article
Synthesis of a Ni Complex Chelated by a [2.2]Paracyclophane-Functionalized Diimine Ligand and Its Catalytic Activity for Olefin Oligomerization
by Daisuke Takeuchi, Yoshi-aki Tojo and Kohtaro Osakada
Molecules 2021, 26(9), 2719; https://doi.org/10.3390/molecules26092719 - 5 May 2021
Cited by 1 | Viewed by 2092
Abstract
A diimine ligand having two [2.2]paracyclophanyl substituents at the N atoms (L1) was prepared from the reaction of amino[2.2]paracyclophane with acenaphtenequinone. The ligand reacts with NiBr2(dme) (dme: 1,2-dimethoxyethane) to form the dibromonickel complex with (R,R) [...] Read more.
A diimine ligand having two [2.2]paracyclophanyl substituents at the N atoms (L1) was prepared from the reaction of amino[2.2]paracyclophane with acenaphtenequinone. The ligand reacts with NiBr2(dme) (dme: 1,2-dimethoxyethane) to form the dibromonickel complex with (R,R) and (S,S) configuration, NiBr2(L1). The structure of the complex was confirmed by X-ray crystallography. NiBr2(L1) catalyzes oligomerization of ethylene in the presence of methylaluminoxane (MAO) co-catalyst at 10–50 °C to form a mixture of 1- and 2-butenes after 3 h. The reactions for 6 h and 8 h at 25 °C causes further increase of 2-butene formed via isomerization of 1-butene and formation of hexenes. Reaction of 1-hexene catalyzed by NiBr2(L1)–MAO produces 2-hexene via isomerization and C12 and C18 hydrocarbons via oligomerization. Consumption of 1-hexene of the reaction obeys first-order kinetics. The kinetic parameters were obtained to be ΔG = 93.6 kJ mol−1, ΔH = 63.0 kJ mol−1, and ΔS = −112 J mol−1deg−1. NiBr2(L1) catalyzes co-dimerization of ethylene and 1-hexene to form C8 hydrocarbons with higher rate and selectivity than the tetramerization of ethylene. Full article
(This article belongs to the Special Issue Ligands in Catalysis)
Show Figures

Figure 1

Review

Jump to: Research

68 pages, 20367 KiB  
Review
Recent Advances in Catalysis Involving Bidentate N-Heterocyclic Carbene Ligands
by Abdollah Neshat, Piero Mastrorilli and Ali Mousavizadeh Mobarakeh
Molecules 2022, 27(1), 95; https://doi.org/10.3390/molecules27010095 - 24 Dec 2021
Cited by 18 | Viewed by 5823
Abstract
Since the discovery of persistent carbenes by the isolation of 1,3-di-l-adamantylimidazol-2-ylidene by Arduengo and coworkers, we witnessed a fast growth in the design and applications of this class of ligands and their metal complexes. Modular synthesis and ease of electronic and steric adjustability [...] Read more.
Since the discovery of persistent carbenes by the isolation of 1,3-di-l-adamantylimidazol-2-ylidene by Arduengo and coworkers, we witnessed a fast growth in the design and applications of this class of ligands and their metal complexes. Modular synthesis and ease of electronic and steric adjustability made this class of sigma donors highly popular among chemists. While the nature of the metal-carbon bond in transition metal complexes bearing N-heterocyclic carbenes (NHCs) is predominantly considered to be neutral sigma or dative bonds, the strength of the bond is highly dependent on the energy match between the highest occupied molecular orbital (HOMO) of the NHC ligand and that of the metal ion. Because of their versatility, the coordination chemistry of NHC ligands with was explored with almost all transition metal ions. Other than the transition metals, NHCs are also capable of establishing a chemical bond with the main group elements. The advances in the catalytic applications of the NHC ligands linked with a second tether are discussed. For clarity, more frequently targeted catalytic reactions are considered first. Carbon–carbon coupling reactions, transfer hydrogenation of alkenes and carbonyl compounds, ketone hydrosilylation, and chiral catalysis are among highly popular reactions. Areas where the efficacy of the NHC based catalytic systems were explored to a lesser extent include CO2 reduction, C-H borylation, alkyl amination, and hydroamination reactions. Furthermore, the synthesis and applications of transition metal complexes are covered. Full article
(This article belongs to the Special Issue Ligands in Catalysis)
Show Figures

Figure 1

Back to TopTop