A DFT study on photoinduced surface catalytic coupling reactions on nanostructured silver: selective formation of azobenzene derivatives from para-substituted nitrobenzene and aniline

Herein we report the use of manganese(II) chloride for the catalytic generation of C(sp2)–C(sp3) bonds via Kumada cross-coupling. Rapid and selective formation of 2-alkylated N-heterocyclic complexes were observed in high yields with use of 3 mol% MnCl2THF1.6 and under ambient reaction conditions (21 °C, 15 min to 20 h). Manganese-catalyzed cross-coupling is tolerant toward both electron-donating and electron-withdrawing functional groups in the 5-position of the pyridine ring, with the latter resulting in an increased reaction rate and a decrease in the amount of nucleophile required. The use of this biologically and environmentally benign metal salt as a catalyst for C–C bond formation highlights its potential as a catalyst for the late-stage functionalization of pharmaceutically active N-heterocyclic molecules (e.g., pyridine, pyrazine).

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Synthesis of functionalised fluorinated pyridine derivatives by site-selective Suzuki-Miyaura cross-coupling reactions of halogenated pyridines

Zeitschrift für Naturforschung B ◽

10.1515/znb-2016-0213 ◽

2017 ◽

Vol 72 (4) ◽

pp. 263-279 ◽

Cited By ~ 1

Author(s):

Muhammad Sharif ◽

Khurram Shoaib ◽

Shahzad Ahmed ◽

Sebastian Reimann ◽

Jamshed Iqbal ◽

...

Keyword(s):

Cross Coupling ◽

Phosphine Ligands ◽

Coupling Reactions ◽

Pyridine Derivatives ◽

One Pot ◽

Arylboronic Acids ◽

Cross Coupling Reactions ◽

The One ◽

Site Selective ◽

Selective Formation

AbstractThe Suzuki-Miyaura reaction of 2,6-dichloro-3-(trifluoromethyl)pyridine with 1 equiv of arylboronic acids resulted in site-selective formation of 2-aryl-6-chloro-3-(trifluoromethyl)pyridine. Due to electronic reasons, the reaction takes place at the sterically more hindered position. The selectivity was rationalised by DFT calculations. The one-pot reaction with two different arylboronic acids afforded 2,6-diaryl-3-(trifluoromethyl)pyridine containing two different aryl substituents. The reactions proceeded smoothly in the absence of phosphine ligands. In addition, Suzuki-Miyaura reactions of 2,6-dichloro-4-(trifluoromethyl)pyridine with one or two equivalents of arylboronic acids were carried out.

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A DFT Study on Selected Physical Organic Aspects of the Fischer Carbene Intermediates [(M(CO)4(C(OMe)Me)]

E-Journal of Chemistry ◽

10.1155/2010/202161 ◽

2010 ◽

Vol 7 (2) ◽

pp. 437-444 ◽

Cited By ~ 1

Author(s):

Tareq Irshaidat

Keyword(s):

Structural Parameters ◽

Dft Study ◽

Free Form ◽

Orbital Interaction ◽

Coupling Reactions ◽

Fischer Carbene ◽

Agostic Interaction ◽

Physical Organic ◽

Fischer Carbenes ◽

Shed Light

Fischer carbenes are important starting materials for C-C bond formation via coupling reactions between carbene and wide variety of substituted alkenes or alkynes. This DFT study shed light on unique fundamental organic/organometallic aspects for the C(OMe)Me carbene in the free form and in case of bonding with M(CO)4(M= Cr, Mo, W). The data illustrate that the structures of the title intermediates include a unique structure stabilizing intramolecular M…C-H interaction (agostic interaction). This conclusion was made based on calculated NMR data (for carbon and hydrogen), structural parameters, energy calculations of conformers (C-C conformation), selected IR stretching frequencies (C-O, C-C, and C-H), and atomic charges. The agostic interaction is most efficient in case of chromium and in general is described as an overlap between the σ-bond electron pair of C-H with an empty d-orbital of the metal. These characterized examples are new addition to the orbital interaction theory.

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