Highly Efficient N-Heterocyclic Carbene/Ruthenium Catalytic Systems for the Acceptorless Dehydrogenation of Alcohols to Carboxylic Acids: Effects of Ancillary and Additional Ligands

The transition-metal-catalyzed alcohol dehydrogenation to carboxylic acids has been identified as an atom-economical and attractive process. Among various catalytic systems, Ru-based systems have been the most accessed and investigated ones. With our growing interest in the discovery of new Ru catalysts comprising N-heterocyclic carbene (NHC) ligands for the dehydrogenative reactions of alcohols, we designed and prepared five NHC/Ru complexes ([Ru]-1–[Ru]-5) bearing different ancillary NHC ligands. Moreover, the effects of ancillary and additional ligands on the alcohol dehydrogenation with KOH were thoroughly explored, followed by the screening of other parameters. Accordingly, a highly active catalytic system, which is composed of [Ru]-5 combined with an additional NHC precursor L5, was discovered, affording a variety of acid products in a highly efficient manner. Gratifyingly, an extremely low Ru loading (125 ppm) and the maximum TOF value until now (4800) were obtained.

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Ruthenium-Based Catalytic Systems Incorporating a Labile Cyclooctadiene Ligand with N-Heterocyclic Carbene Precursors for the Atom-Economic Alcohol Amidation Using Amines

Molecules ◽

10.3390/molecules23102413 ◽

2018 ◽

Vol 23 (10) ◽

pp. 2413 ◽

Cited By ~ 7

Author(s):

Cheng Chen ◽

Yang Miao ◽

Kimmy De Winter ◽

Hua-Jing Wang ◽

Patrick Demeyere ◽

...

Keyword(s):

Catalytic System ◽

High Resolution Mass Spectrometry ◽

Amide Bond ◽

Catalyst Loading ◽

Catalytic Systems ◽

Amide Bond Formation ◽

Highly Active ◽

Metal Catalyzed ◽

Ru Species

Transition-metal-catalyzed amide-bond formation from alcohols and amines is an atom-economic and eco-friendly route. Herein, we identified a highly active in situ N-heterocyclic carbene (NHC)/ruthenium (Ru) catalytic system for this amide synthesis. Various substrates, including sterically hindered ones, could be directly transformed into the corresponding amides with the catalyst loading as low as 0.25 mol.%. In this system, we replaced the p-cymene ligand of the Ru source with a relatively labile cyclooctadiene (cod) ligand so as to more efficiently obtain the corresponding poly-carbene Ru species. Expectedly, the weaker cod ligand could be more easily substituted with multiple mono-NHC ligands. Further high-resolution mass spectrometry (HRMS) analyses revealed that two tetra-carbene complexes were probably generated from the in situ catalytic system.

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Ruthenium-Based Catalytic Systems Incorporating a Labile Cyclooctadiene Ligand with N-Heterocyclic Carbene Precursors for the Atom-Economic Alcohol Amidation Using Amines.

10.20944/preprints201808.0495.v1 ◽

2018 ◽

Author(s):

Cheng Chen ◽

Yang Miao ◽

Kimmy De Winter ◽

Hua-Jing Wang ◽

Patrick Demeyere ◽

...

Keyword(s):

Catalytic System ◽

Amide Bond ◽

Catalyst Loading ◽

Catalytic Systems ◽

Carbene Complexes ◽

Amide Bond Formation ◽

Highly Active ◽

Metal Catalyzed ◽

Ru Species

Transition-metal-catalyzed amide bond formation from alcohols and amines is an atom-economic and eco-friendly route. Herein, we identified a highly active in situ N-heterocyclic carbene (NHC)/ruthenium (Ru) catalytic system for this amide synthesis. Various substrates, including sterically hindered ones, could be directly transformed into the corresponding amides with the catalyst loading as low as 0.25 mol%. In this system, we replaced the p-cymene ligand of the Ru source with a relatively labile cyclooctadiene (cod) ligand so as to more efficiently obtain the corresponding poly-carbene Ru species. Expectedly, the weaker cod ligand could be more easily substituted with multiple mono-NHC ligands. Further HR-MS analyses revealed that two tetra-carbene complexes were probably generated from the in situ catalytic system.

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Highly Active and Removable Ruthenium Catalysts for Transition-Metal-Catalyzed Living Radical Polymerization: Design of Ligands and Cocatalysts

Chemistry - An Asian Journal ◽

10.1002/asia.200800142 ◽

2008 ◽

Vol 3 (8-9) ◽

pp. 1358-1364 ◽

Cited By ~ 26

Author(s):

Makoto Ouchi ◽

Makoto Ito ◽

Satoshi Kamemoto ◽

Mitsuo Sawamoto

Keyword(s):

Transition Metal ◽

Radical Polymerization ◽

Living Radical Polymerization ◽

Ruthenium Catalysts ◽

Highly Active ◽

Transition Metal Catalyzed ◽

Metal Catalyzed

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Transition Metal-Catalyzed α-Position Carbon–Carbon Bond Formations of Carbonyl Derivatives

Catalysts ◽

10.3390/catal10080861 ◽

2020 ◽

Vol 10 (8) ◽

pp. 861 ◽

Cited By ~ 1

Author(s):

Ha-Eun Lee ◽

Dopil Kim ◽

Ahrom You ◽

Myung Hwan Park ◽

Min Kim ◽

...

Keyword(s):

Transition Metal ◽

Carbonyl Compounds ◽

Bond Formation ◽

Chiral Ligand ◽

Catalytic Systems ◽

Carbon Bond ◽

Carbonyl Derivatives ◽

Carbon Carbon Bond ◽

Transition Metal Catalyzed ◽

Metal Catalyzed

α-Functionalization of carbonyl compounds in organic synthesis has traditionally been accomplished via classical enolate chemistry. As α-functionalized carbonyl moieties are ubiquitous in biologically and pharmaceutically valuable molecules, catalytic α-alkylations have been extensively studied, yielding a plethora of practical and efficient methodologies. Moreover, stereoselective carbon–carbon bond formation at the α-position of achiral carbonyl compounds has been achieved by using various transition metal–chiral ligand complexes. This review describes recent advances—in the last 20 years and especially focusing on the last 10 years—in transition metal-catalyzed α-alkylations of carbonyl compounds, such as aldehydes, ketones, imines, esters, and amides and in efficient carbon–carbon bond formations. Active catalytic species and ligand design are discussed, and mechanistic insights are presented. In addition, recently developed photo-redox catalytic systems for α-alkylations are described as a versatile synthetic tool for the synthesis of chiral carbonyl-bearing molecules.

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Highly active, chemo- and enantioselective Pt-SPO catalytic systems for the synthesis of aromatic carboxamides

Catalysis Science & Technology ◽

10.1039/c5cy00627a ◽

2015 ◽

Vol 5 (7) ◽

pp. 3822-3828 ◽

Cited By ~ 13

Author(s):

Henrik Gulyás ◽

Ivan Rivilla ◽

Simona Curreli ◽

Zoraida Freixa ◽

Piet W. N. M. van Leeuwen

Keyword(s):

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Kinetic Resolution ◽

Platinum Complexes ◽

Catalytic Systems ◽

Highly Active

Platinum complexes of the chiral non-racemizing SPO ligand 1 have been discovered to be the first artificial transition metal complexes providing kinetic resolution in the hydration of a racemic chiral nitrile.

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Catalytic Asymmetric Amino Acid and Its Derivatives by Chiral Aldehyde Catalysis

Frontiers in Chemistry ◽

10.3389/fchem.2021.687817 ◽

2021 ◽

Vol 9 ◽

Author(s):

Kaijin Lin ◽

Ang Shi ◽

Chunhong Shi ◽

Jinbiao Lin ◽

Honggui Lin

Keyword(s):

Amino Acid ◽

Transition Metal ◽

Catalytic System ◽

Chemical Process ◽

Amino Acid Esters ◽

Asymmetric Reaction ◽

Catalytic Systems ◽

Catalytic Activation ◽

The Face ◽

Acid Esters

Amine acid transformation is an important chemical process in biological systems. As a well-developed and acknowledged tool, chiral aldehyde catalysis provides good catalytic activation and stereoselective control abilities in the asymmetric reaction of N-unprotected amino acid esters and amino acid esters analogs, in which the key to success is the design of the catalysts derived from chiral BINOL aldehyde, which is based on the face control of enolate intermediates. In this review, one of the co-catalytic systems that combined with a transition metal to form a multiplex catalytic system and the well-established multiplex stereocenters of chiral aldehyde catalysis have been reviewed. Finally, a novel organocatalysis is prospected.

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Fast Carbon Isotope Exchange of Carboxylic Acids Enabled by Organic Photoredox Catalysis

10.26434/chemrxiv.13111505 ◽

2020 ◽

Author(s):

Duanyang Kong ◽

Maxime Munch ◽

Qiqige Qiqige ◽

Christopher Cooze ◽

Benjamin Rotstein ◽

...

Keyword(s):

Transition Metal ◽

Carbon Isotope ◽

Carboxylic Acids ◽

Isotope Exchange ◽

Room Temperature ◽

Reaction Times ◽

Thermally Induced ◽

Drug Molecules ◽

Metal Catalyzed ◽

Isotopic Incorporation

Carbazole/cyanobenzene photocatalysts promote the direct isotopic carboxylate exchange of C(sp3 )-acids with labelled CO2. Substrates that are not compatible with transition metal catalyzed degradation-reconstruction approaches or prone to thermally induced reversible decarboxylation undergo isotopic incorporation at room temperature in short reaction times. The radiolabelling of drug molecules and precursors with [11C]CO2 is demonstrated.

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Cu(I)-Bis(phosphine) Dioxides as catalysts for the Enantioselective α-Arylation of Carbonyl Compounds

Synlett ◽

10.1055/a-1503-7339 ◽

2021 ◽

Author(s):

Margarita Escudero-Casao ◽

Giulia Licini ◽

Manuel Orlandi

Keyword(s):

Reaction Mechanism ◽

Transition Metal ◽

Catalytic System ◽

Carbonyl Compounds ◽

Research Area ◽

Metal Catalysts ◽

Transition Metal Catalysts ◽

Transition Metal Catalyzed ◽

Metal Catalyzed

The transition metal catalyzed α-arylation of carbonyl compounds was first reported by Buchwald and Hartwig in 1997. This transformation has been used and studied extensively over the last two decades. Enantioselective variants were also developed that allow for controlling the product stereochemistry. However, these suffer several limitations in the context of formation of tertiary stereocenters. Presented here is our group’s contribution to this research area. The chiral Cu-bis(phosphine) dioxides catalytic system that we reported allowed accessing the enantioselective α-arylation of ketones that were not suitable for this transformation before in good yields and er up to 97.5:2.5. Preliminary insight and speculation concerning the reaction mechanism involving the unusual pairing of bis(phosphine) dioxides with transition metal catalysts is also given.

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Recent Advances in the Transition Metal Catalyzed Addition of Carboxylic Acids to Alkynes

Current Organic Chemistry ◽

10.2174/1385272825666210308113837 ◽

2021 ◽

Vol 25 ◽

Author(s):

Victorio Cadierno

Keyword(s):

Natural Products ◽

Transition Metal ◽

Carboxylic Acids ◽

Heterocyclic Compounds ◽

Biologically Active ◽

Recent Advances ◽

Enol Esters ◽

Cascade Processes ◽

Transition Metal Catalyzed ◽

Metal Catalyzed

: Recent advances in the metal-catalyzed hydrofunctionalization of alkynes with carboxylic acids are comprehensively reviewed. Both inter- and intramolecular processes, leading respectively to enol esters and lactones, are discussed, as well as the involvement of these transformations in the synthesis of natural products and biologically active molecules, and the assembly of elaborated heterocyclic compounds though cascade processes. Literature published since 2011 is covered.

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