scholarly journals Oxidant speciation and anionic ligand effects in the gold-catalyzed oxidative coupling of arenes and alkynes

2019 ◽  
Vol 10 (36) ◽  
pp. 8411-8420 ◽  
Author(s):  
Manuel Hofer ◽  
Teresa de Haro ◽  
Enrique Gómez-Bengoa ◽  
Alexandre Genoux ◽  
Cristina Nevado
Keyword(s):  
Dft Calculations ◽  
Oxidative Coupling ◽  
Cross Coupling ◽  
Reaction Intermediates ◽  
Ligand Effects ◽  
Anionic Ligand

The mechanism of the gold-catalyzed oxidative cross-coupling of arenes and alkynes has been studied in detail combining stoichiometric experiments with putative reaction intermediates and DFT calculations.

Dilithium Amides as a Modular Bis-Anionic Ligand Platform for Iron-Catalyzed Cross-Coupling

2021 ◽  
Author(s):  
Peter G. N. Neate ◽  
Bufan Zhang ◽  
Jessica Conforti ◽  
William W. Brennessel ◽  
Michael L. Neidig
Keyword(s):  
Cross Coupling ◽  
Anionic Ligand

Tropylium Salt Promoted Hydroboration Reactions: Mechanistic Insights via Experimental and Computational Studies

2021 ◽  
Author(s):  
Nhan Nu Hong Ton ◽  
Binh Khanh Mai ◽  
Thanh Vinh Nguyen
Keyword(s):  
Dft Calculations ◽  
Lewis Acids ◽  
Experimental Studies ◽  
Cross Coupling ◽  
Computational Studies ◽  
Metal Free ◽  
Hydride Abstraction ◽  
Novel Method ◽  
Tropylium Salts

Abstract: Hydroboration reaction of alkynes is one of the most synthetically powerful tools to access organoboron compounds, versatile precursors for cross coupling chemistry. This type of reaction has traditionally been mediated by transition metal or main group catalysts. Herein, we report a novel method using tropylium salts, typically known as organic oxidants and Lewis acids, to efficiently promote the hydroboration reaction of alkynes. A broad range of vinylboranes can be easily accessed via this metal-free protocol. Similar hydroboration reactions of alkenes and epoxides can also be efficiently catalyzed by the same tropylium catalysts. Experimental studies and DFT calculations suggested that the reaction follows an uncommon mechanistic paradigm, which is triggered by a hydride abstraction of pinacolborane with tropylium ion. This is followed by a series of <i>in situ</i> counterion-activated substituent exchanges to generate boron intermediates that promote the hydroboration reaction.

Key Role of π–π Complex in Diary Cross-Coupling between Aryldiazonium Salts and Arylboronic Acids using Photosensitizer-Free Gold/Photoredox Catalysis

2021 ◽  
Author(s):  
Yanhong Liu ◽  
Rong-Xiu Zhu ◽  
Chengbu Liu ◽  
Dongju Zhang
Keyword(s):  
Dft Calculations ◽  
Visible Light ◽  
Cross Coupling ◽  
Photoredox Catalysis ◽  
Arylboronic Acids ◽  
Type Complex ◽  
Free Gold ◽  
Π Complex ◽  
Td Dft

DFT and TD-DFT calculations were performed to better understand the photosensitizer-free visible-light-mediated Au-catalyzed cross-couplings between aryldiazonium salts and arylboronic acids. The π–π type complex between the aryldiazonium salt and the...

How electron-deficient Cp ligand facilitates Rh-catalyzed annulations with alkynes

2022 ◽  
Author(s):  
Han Gao ◽  
Lingfei Hu ◽  
Yanlei Hu ◽  
Xiangying Lv ◽  
Yanbo Wu ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Decomposition Analysis ◽  
Energy Decomposition Analysis ◽  
Energy Decomposition ◽  
Ligand Effects

The mechanism and origin of CpX ligand effects on Rh-catalyzed annulations with alkynes were investigated by using DFT calculations and the approach of energy decomposition analysis (EDA). The results reveal...

KI-Promoted Oxidative Coupling of Styrenes with Indoles under Metal-Free Conditions: Facile Access to C-3 Dicarbonyl Indoles

Synthesis ◽  
2019 ◽  
Vol 51 (18) ◽  
pp. 3511-3519
Author(s):  
Bochao Zhou ◽  
Shiyu Guo ◽  
Zheng Fang ◽  
Zhao Yang ◽  
Chengkou Liu ◽  
...  
Keyword(s):  
Efficient Method ◽  
Oxidative Coupling ◽  
Isotope Labeling ◽  
Cross Coupling ◽  
Metal Free ◽  
Broad Scope ◽  
Plausible Mechanism ◽  
Isotope Labeling Experiments

A new and efficient method for the synthesis of C-3 dicarbonyl indoles via oxidative cross-coupling of styrenes with indoles under metal-free conditions has been developed. Moreover, a broad scope of C-3 dicarbonyl indoles in moderate to good yields were obtained, and a plausible mechanism is proposed based on control and isotope-labeling experiments.

Origin of stereoselectivity and multidimensional quantitative analysis of ligand effects on yttrium-catalysed polymerization of 2-vinylpyridine

2019 ◽  
Vol 9 (22) ◽  
pp. 6227-6233 ◽  
Author(s):  
Yanan Zhao ◽  
Han Lu ◽  
Gen Luo ◽  
Xiaohui Kang ◽  
Zhaomin Hou ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Regression Analysis ◽  
Quantitative Analysis ◽  
Dft Calculations ◽  
Multivariate Regression ◽  
Density Functional ◽  
Multivariate Regression Analysis ◽  
Functional Theory ◽  
Ligand Effects

Through a combination of density functional theory (DFT) calculations and multivariate regression analysis, the origin of the stereoselectivity of yttrium-catalysed polymerization of 2-vinylpyridine (2VP) has been investigated.

Iodine mediated oxidative cross coupling of 2-aminopyridine and aromatic terminal alkyne: a practical route to imidazo[1,2-a]pyridine derivatives

2019 ◽  
Vol 17 (26) ◽  
pp. 6441-6449 ◽  
Author(s):  
Surya Kanta Samanta ◽  
Mrinal K. Bera
Keyword(s):  
Transition Metal ◽  
Oxidative Coupling ◽  
Cross Coupling ◽  
Terminal Alkyne ◽  
Pyridine Derivatives ◽  
Metal Free

A novel, transition-metal free route leading to imidazo[1,2-a]pyridine derivatives via iodine mediated oxidative coupling between 2-aminopyridine and aromatic terminal alkyne has been demonstrated.

scholarly journals Isoxazolium N-ylides and 1-oxa-5-azahexa-1,3,5-trienes on the way from isoxazoles to 2H-1,3-oxazines

2014 ◽  
Vol 10 ◽  
pp. 1896-1905 ◽  
Author(s):  
Alexander F Khlebnikov ◽  
Mikhail S Novikov ◽  
Yelizaveta G Gorbunova ◽  
Ekaterina E Galenko ◽  
Kirill I Mikhailov ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Experimental Studies ◽  
Diazo Compounds ◽  
Stationary Points ◽  
Reaction Intermediates ◽  
Reaction Conditions ◽  
Open Chain ◽  
Isoxazole Ring ◽  
Diazo Esters ◽  
Probable Reaction

Theoretical and experimental studies of the reaction of isoxazoles with diazo compounds show that the formation of 2H-1,3-oxazines proceeds via the formation of (3Z)-1-oxa-5-azahexa-1,3,5-trienes which undergo a 6π-cyclization. The stationary points corresponding to the probable reaction intermediates, isoxazolium N-ylides, were located by DFT calculations at the B3LYP/6-31G(d) level only for derivatives without a substituent in position 3 of the isoxazole ring. These isoxazolium N-ylides are thermodynamically and kinetically very unstable. According to the calculations and experimental results 2H-1,3-oxazines are usually more thermodynamically stable than the corresponding open-chain isomers, (3Z)-1-oxa-5-azahexa-1,3,5-trienes. The exception are oxaazahexatrienes derived from 5-alkoxyisoxazoles, which are thermodynamically more stable than the corresponding 2H-1,3-oxazines. Therefore, the reaction of diazo esters with 5-alkoxyisoxazoles is a good approach to 1,4-di(alkoxycarbonyl)-2-azabuta-1,3-dienes. The reaction conditions for the preparation of aryl- and halogen-substituted 2H-1,3-oxazines and 1,4-di(alkoxycarbonyl)-2-azabuta-1,3-dienes from isoxazoles were investigated.

Oxidative coupling of Michael acceptors with aryl nucleophiles produced through rhodium-catalyzed C–C bond activation

2017 ◽  
Vol 15 (28) ◽  
pp. 5944-5948 ◽  
Author(s):  
Caroline E. Gregerson ◽  
Kathryn N. Trentadue ◽  
Erik J. T. Phipps ◽  
Janelle K. Kirsch ◽  
Katherine M. Reed ◽  
...  
Keyword(s):  
Oxidative Coupling ◽  
Bond Activation ◽  
Cross Coupling ◽  
Michael Acceptors

C–C bond activation generates aryl nucleophiles for cross-coupling.

Sign in / Sign up

Export Citation Format

Share Document