Key factors in pincer ligand design

2018 ◽  
Vol 47 (6) ◽  
pp. 1959-1968 ◽  
Author(s):  
Eduardo Peris ◽  
Robert H. Crabtree
Keyword(s):  
Ligand Design ◽  
Pincer Ligands ◽  
Key Factors ◽  
Pincer Ligand

This tutorial review analyses the reasons of success of pincer ligands.

Lowering the Barrier to C–H Activation at IrIII through Pincer Ligand Design

2021 ◽  
Author(s):  
Sophie B. Rubashkin ◽  
Wan-Yi Chu ◽  
Karen I. Goldberg
Keyword(s):  
Ligand Design ◽  
Pincer Ligand

scholarly journals Iron Complexes of a Proton-Responsive SCS Pincer Ligand with Sensitive Electronic Structure

2021 ◽  
Author(s):  
Kazimer Skubi ◽  
Reagan Hooper ◽  
Brandon Mercado ◽  
Melissa Bollmeyer ◽  
Samantha MacMillan ◽  
...  
Keyword(s):  
Strong Field ◽  
Alkali Metal Cation ◽  
Weak Field ◽  
Pincer Ligands ◽  
Zero Field ◽  
Zero Field Splitting ◽  
Pincer Ligand ◽  
Intermediate Spin ◽  
X Ray Absorption ◽  
Phosphine Complex

SCS pincer ligands have an interesting combination of strong-field and weak-field donors that is also present in the nitrogenase active site. Here, we explore the electronic structures of iron(II) and iron(III) complexes with such a pincer ligand, bearing a monodentate phosphine, thiolate S donor, amide N donor, ammonia, or CO. The ligand scaffold features a protonresponsive thioamide site, and the protonation state of the ligand greatly influences the reduction potential of iron in the phosphine complex. The N–H bond dissociation free energy can be quantitated as 56 ± 2 kcal/mol. EPR spectroscopy and SQUID magnetometry measurements show that the iron(III) complexes with S and N as the fourth donors have an intermediate spin (S = 3/2) ground state with large zero field splitting, and X-ray absorption spectra show high Fe–S covalency. The Mössbauer spectrum changes drastically with the position of a nearby alkali metal cation in the iron(III) amido complex, and DFT calculations explain this phenomenon through a change between having the doubly-occupied orbital as dz2 or dyz, as the former is more influenced by the nearby positive charge.

Aldehyde effect and ligand discovery in Ru-catalyzed dehydrogenative cross-coupling of alcohols to esters

2019 ◽  
Vol 55 (19) ◽  
pp. 2797-2800 ◽  
Author(s):  
Xiaolin Jiang ◽  
Jiahui Zhang ◽  
Dongmei Zhao ◽  
Yuehui Li
Keyword(s):  
Cross Coupling ◽  
Ligand Design ◽  
Pincer Ligands ◽  
Ligand Discovery ◽  
Dehydrogenation Reactions

An aldehyde effect was discovered and utilized for ligand design in dehydrogenation reactions using PN(H)P pincer ligands.

scholarly journals Monomeric alkoxide and alkylcarbonate complexes of nickel and palladium stabilized with the iPrPCP pincer ligand: a model for the catalytic carboxylation of alcohols to alkyl carbonates

2019 ◽  
Vol 48 (4) ◽  
pp. 1351-1366 ◽  
Author(s):  
Luis M. Martínez-Prieto ◽  
Pilar Palma ◽  
Juan Cámpora
Keyword(s):  
Catalytic Synthesis ◽  
Pincer Ligands ◽  
Pincer Ligand ◽  
Organic Carbonates ◽  
Key Steps

Monomeric nickel and palladium alkoxides stabilized with pincer ligands provide a model for the study of key steps in the catalytic synthesis of organic carbonates from alcohols and CO2.

scholarly journals Silver(i), gold(i) and palladium(ii) complexes of a NHC-pincer ligand with an aminotriazine core: a comparison with pyridyl analogues

2016 ◽  
Vol 45 (4) ◽  
pp. 1484-1495 ◽  
Author(s):  
Jamila Vaughan ◽  
Damien J. Carter ◽  
Andrew L. Rohl ◽  
Mark I. Ogden ◽  
Brian W. Skelton ◽  
...  
Keyword(s):  
Pincer Ligands ◽  
Computational Studies ◽  
Pincer Ligand ◽  
Gold Complexes

The twisted vs. linear conformation of newly synthesised silver and gold complexes of chelating C,N,C diethylaminotriazinyl-bridged bis(NHC) pincer ligands have been rationalised by computational studies.

scholarly journals Group 11 Pincer Oxazoline Complexes

2021 ◽  
Author(s):  
Mahroo T. Seighalani
Keyword(s):  
Point Group ◽  
Diffraction Method ◽  
Binding Mode ◽  
Group Symmetry ◽  
Pincer Complexes ◽  
Pincer Ligands ◽  
Henry Reaction ◽  
X Ray Diffraction ◽  
Pincer Ligand ◽  
Nitroaldol Reaction

The synthesis and characterization of new copper pincer complexes via cyclometallation of potentially anionic pincer ligands with C1 point group symmetry is reported. All of these complexes have been characterized by single crystal X-ray diffraction method, which confirms the proposed tridentate binding mode of pincer ligand and the formation of an amido N-Cu bond. The reactivity of two of the complexes was investigated towards C-C bond formation reaction, notably the Henry reaction. One of the complexes, which was derived from the achiral pincer ligand, is shown to be a suitable catalyst for the Henry reaction under the standard conditions. The Henry or nitroaldol reaction is one of the organic reactions which affords a C-C bond. The product of this reaction is a β-nitro alcohol which is formed by addition of a nitroalkane to a carbonyl compound.

scholarly journals Ammonia Formation Catalyzed by Dinitrogen-Bridged Dirhenium Complex Bearing PNP-Pincer Ligands under Mild Reaction Conditions

2020 ◽  
Author(s):  
Fanqiang Meng ◽  
Shogo Kuriyama ◽  
Hiromasa Tanaka ◽  
Akihito Egi ◽  
Kazunari Yoshizawa ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Pincer Ligands ◽  
Pincer Ligand ◽  
Reaction Conditions ◽  
Rhenium Atom ◽  
Phosphine Complexes ◽  
Proton Source ◽  
Dinitrogen Complexes ◽  
Dinitrogen Complex ◽  
Ammonia Formation

A series of rhenium complexes bearing a pyridine-based PNP-type pincer ligand are synthesized from rhenium phosphine complexes as precursors. A dinitrogen-bridged dirhenium complex bearing the PNP-type pincer ligands catalytically converts dinitrogen into ammonia in the reaction with KC<sub>8</sub> as a reductant and [HPCy<sub>3</sub>]BAr<sup>F</sup><sub>4</sub> (Cy = cyclohexyl, Ar<sup>F</sup> = 3,5-(CF<sub>3</sub>)<sub>2</sub>C<sub>6</sub>H<sub>3</sub>) as a proton source at –78 °C to afford 8.4 equiv of ammonia based on the rhenium atom of the catalyst. The rhenium-dinitrogen complex also catalyzes silylation of dinitrogen in the reaction with KC<sub>8</sub> as a reductant and Me<sub>3</sub>SiCl as a silylating reagent under ambient reaction conditions to afford 11.3 equiv of tris(trimethylsilyl)amine based on the rhenium atom of the catalyst. These results demonstrate the first successful example of catalytic nitrogen fixation under mild reaction conditions by using rhenium-dinitrogen complexes as catalysts.

scholarly journals Group 11 Pincer Oxazoline Complexes

2021 ◽  
Author(s):  
Mahroo T. Seighalani
Keyword(s):  
Point Group ◽  
Diffraction Method ◽  
Binding Mode ◽  
Group Symmetry ◽  
Pincer Complexes ◽  
Pincer Ligands ◽  
Henry Reaction ◽  
X Ray Diffraction ◽  
Pincer Ligand ◽  
Nitroaldol Reaction

The synthesis and characterization of new copper pincer complexes via cyclometallation of potentially anionic pincer ligands with C1 point group symmetry is reported. All of these complexes have been characterized by single crystal X-ray diffraction method, which confirms the proposed tridentate binding mode of pincer ligand and the formation of an amido N-Cu bond. The reactivity of two of the complexes was investigated towards C-C bond formation reaction, notably the Henry reaction. One of the complexes, which was derived from the achiral pincer ligand, is shown to be a suitable catalyst for the Henry reaction under the standard conditions. The Henry or nitroaldol reaction is one of the organic reactions which affords a C-C bond. The product of this reaction is a β-nitro alcohol which is formed by addition of a nitroalkane to a carbonyl compound.

Sign in / Sign up

Export Citation Format

Share Document