Phosphine-Free Well-Defined Mn(I) Complex-Catalyzed Synthesis of Amine, Imine, and 2,3-Dihydro-1H-perimidine via Hydrogen Autotransfer or Acceptorless Dehydrogenative Coupling of Amine and Alcohol DOI
Kalicharan Das, Avijit Mondal,

Debjyoti Pal

et al.

Organometallics, Journal Year: 2019, Volume and Issue: 38(8), P. 1815 - 1825

Published: April 12, 2019

The application of nontoxic, earth-abundant transition metals in place costly noble is a paramount goal catalysis and especially interesting if the air- moisture-stable ligand scaffold used. Herein, we report synthesis amines/imines directly from alcohol amines via hydrogen autotransfer or acceptorless dehydrogenation catalyzed by well-defined phosphine-free Mn complexes. Both imines can be obtained same set alcohols using catalyst, only tuning reaction conditions. amount nature base are found to highly important aspect for observed selectivity. primary secondary have been employed as substrates N-alkylation reaction. As highlight, showed chemoselective resveratrol derivatives. Furthermore, Mn-catalyzed dehydrogenative structurally 2,3-dihydro-1H-perimidines has also demonstrated. Density functional theory calculations were carried out model path calculate profile.

Language: Английский

Homogeneously catalyzed acceptorless dehydrogenation of alcohols: A progress report DOI Creative Commons
Mónica Trincado,

Jonas Bösken,

Hansjörg Grützmacher

et al.

Coordination Chemistry Reviews, Journal Year: 2021, Volume and Issue: 443, P. 213967 - 213967

Published: May 24, 2021

Catalytic dehydrogenation of alcohols represents an attractive approach for future applications as hydrogen storage systems and clean synthesis fine chemicals. Herein, overview recent progress in homogeneously catalyzed acceptorless alcohol is presented. In Nature, efficiently by multiple metalloenzymes where a non-noble metal–ligand interplay key to activate transform substrate. We highlight the introduction multifunctional cooperative ligands coordination sphere metal center order improve catalytic activity under photochemical, electrochemical or thermal conditions. Moreover, cooperativity crucial easy transition first row based catalysis, we have seen years.

Language: Английский

Citations

113
Manganese-Catalyzed β-Alkylation of Secondary Alcohols with Primary Alcohols under Phosphine-Free Conditions DOI
Tingting Liu, Liandi Wang, Kaikai Wu

et al.

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(8), P. 7201 - 7207

Published: July 5, 2018

Manganese(I) complexes bearing a pyridyl-supported pyrazolyl-imidazolyl ligand efficiently catalyzed the direct β-alkylation of secondary alcohols with primary under phosphine-free conditions. The β-alkylated were obtained in moderate to good yields water formed as byproduct through borrowing hydrogen pathway. β-Alkylation cholesterols was also effectively achieved. present protocol provides concise atom-economical method for C–C bond formation from and alcohols.

Language: Английский

Citations

159
Phosphine free Mn-complex catalysed dehydrogenative C–C and C–heteroatom bond formation: a sustainable approach to synthesize quinoxaline, pyrazine, benzothiazole and quinoline derivatives DOI
Kalicharan Das, Avijit Mondal, Dipankar Srimani

et al.

Chemical Communications, Journal Year: 2018, Volume and Issue: 54(75), P. 10582 - 10585

Published: Jan. 1, 2018

Sustainable synthesis of quinoxalines, pyrazines, benzothiazoles and quinolines catalysed by a phosphine free Mn(i) complex.

Language: Английский

Citations

155
Phosphine‐Free NNN‐Manganese Complex Catalyzed α‐Alkylation of Ketones with Primary Alcohols and Friedländer Quinoline Synthesis DOI
Milan Kr. Barman, Akash Jana, Biplab Maji

et al.

Advanced Synthesis & Catalysis, Journal Year: 2018, Volume and Issue: 360(17), P. 3233 - 3238

Published: June 29, 2018

Abstract Herein, we report a very simple and inexpensive catalytic system based on Earth's abundant transition metal manganese bench‐stable phosphine‐free NNN‐pincer ligand for an atom‐efficient α‐alkylations of ketones with primary alcohols via hydrogen‐autotransfer C−C bond formation protocol. The precatalyst could be generated in situ activated by using amount base under milder conditions. A range were efficiently diversified broad good to excellent isolated yields. Remarkably, this catalyst also employed the synthesis quinoline derivatives 2‐aminobenzyl alcohol as alkylating agent. later reaction is highly benign producing only hydrogen water byproducts. magnified image

Language: Английский

Citations

148
Manganese‐Catalyzed Dehydrogenative Alkylation or α‐Olefination of Alkyl‐Substituted N‐Heteroarenes with Alcohols DOI
Guoying Zhang, Τ. Irrgang, Thomas Dietel

et al.

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(29), P. 9131 - 9135

Published: May 2, 2018

Catalysis with earth-abundant transition metals is an option to help save our rare noble-metal resources and especially interesting when novel reactivity or selectivity patterns are observed. We report here on a reaction, namely the dehydrogenative alkylation α-olefination of alkyl-substituted N-heteroarenes alcohols. Manganese complexes developed in laboratory catalyze reaction high efficiency whereas iron cobalt stabilized by same ligands essentially inactive. Hydrogen liberated during bromine iodine functional groups as well olefins tolerated. A variety can be functionalized, benzylic aliphatic alcohols undergo reaction.

Language: Английский

Citations

142
Synthesis of Pyrazines and Quinoxalines via Acceptorless Dehydrogenative Coupling Routes Catalyzed by Manganese Pincer Complexes DOI Creative Commons
Prosenjit Daw, Amit Kumar, Noel Ángel Espinosa-Jalapa

et al.

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(9), P. 7734 - 7741

Published: July 23, 2018

Base-metal catalyzed dehydrogenative self-coupling of 2-amino alcohols to selectively form functionalized 2,5-substituted pyrazine derivatives is presented. Also, 2-substituted quinoxaline are synthesized by coupling 1,2-diaminobenzene and 1,2-diols. In both cases, water hydrogen gas formed as the sole byproducts. The reactions acridine-based pincer complexes earth-abundant manganese.

Language: Английский

Citations

139
Selective Synthesis of 2-Substituted and 1,2-Disubstituted Benzimidazoles Directly from Aromatic Diamines and Alcohols Catalyzed by Molecularly Defined Nonphosphine Manganese(I) Complex DOI
Kalicharan Das, Avijit Mondal, Dipankar Srimani

et al.

The Journal of Organic Chemistry, Journal Year: 2018, Volume and Issue: 83(16), P. 9553 - 9560

Published: July 11, 2018

Herein, we present a selective synthesis of 2-substituted and 1,2-disubstituted benzimidazoles by acceptorless dehydrogenative coupling aromatic diamine with primary alcohols. The reaction is catalyzed phosphine-free tridentate NNS ligand-derived manganese(I) complex.

Language: Английский

Citations

138
N‐Substituted Hydrazones by Manganese‐Catalyzed Coupling of Alcohols with Hydrazine: Borrowing Hydrogen and Acceptorless Dehydrogenation in One System DOI
Uttam Kumar Das,

Yehoshoa Ben‐David,

Yael Diskin‐Posner

et al.

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(8), P. 2179 - 2182

Published: Jan. 10, 2018

An unprecedented one-step synthesis of N-substituted hydrazones by coupling alcohols with hydrazine is reported. This partial hydrogen-borrowing reaction catalyzed a new manganese pincer complex under mild conditions, thus liberating water and dihydrogen as the only byproducts. Mechanistic insight, based on observation intermediates, provided.

Language: Английский

Citations

118
Highly Selective, Efficient Deoxygenative Hydrogenation of Amides Catalyzed by a Manganese Pincer Complex via Metal–Ligand Cooperation DOI Creative Commons
You‐Quan Zou, Subrata Chakraborty,

Alexander Nerush

et al.

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(9), P. 8014 - 8019

Published: July 30, 2018

Deoxygenative hydrogenation of amides to amines homogeneously catalyzed by a complex an Earth-abundant metal is presented. This manganese-catalyzed reaction features high efficiency and selectivity. A plausible mechanism, involving metal-ligand cooperation the manganese pincer complex, proposed based on NMR studies relevant stoichiometric reactions.

Language: Английский

Citations

115
Mangankomplexe in der (De)Hydrier‐Katalyse – ein Vergleich mit Cobalt‐ und Eisenkatalysatoren DOI
Fabian Kallmeier, Rhett Kempe

Angewandte Chemie, Journal Year: 2017, Volume and Issue: 130(1), P. 48 - 63

Published: Oct. 24, 2017

Abstract Der nachhaltige Umgang mit den Ressourcen unseres Planeten ist essenziell. Edelmetalle sind sehr selten und werden vielfältig in Schlüsseltechnologien wie der Katalyse genutzt. Mangan das dritthäufigste Übergangsmetall Erdkruste aufgrund seiner kürzlich entdeckten beeindruckenden Reaktivität für Hydrierungen Dehydrierungen ein potenzieller Edelmetall‐“Ersatz”. An einen derartigen “Ersatz” auch Hoffnungen auf neuartige Selektivitätsprofile geknüpft, die Edelmetallen nicht erzielt können. Dass Mangankomplexe eine solche (De)Hydrierungen aufweisen, wurde erstmals 2016 gezeigt. Hier fassen wir seitdem publizierten Arbeiten diesem Gebiet zusammen diskutieren im Besonderen Bedeutung Mangankatalysatoren Vergleich zu Cobalt‐ Eisenkatalysatoren.

Citations

114