Palladium-catalyzed C–H activation of anisole with electron-deficient auxiliary ligands: a mechanistic investigation

2020 ◽  
Vol 18 (30) ◽  
pp. 5857-5866 ◽  
Author(s):  
Xinyu Xu ◽  
Kezhi Chen
Keyword(s):  
Dft Calculations ◽  
Site Selectivity ◽  
Mechanistic Investigation ◽  
Palladium Catalyzed

In this work, the experimentally observed site-selectivity and ligand choice of Yu's meta-arylation reaction were rationalized through DFT calculations.

Theoretical and experimental studies of palladium-catalyzed site-selective C(sp3)−H bond functionalization enabled by transient ligands

2017 ◽  
Author(s):  
Haibo Ge ◽  
Lei Pan ◽  
Piaoping Tang ◽  
Ke Yang ◽  
Mian Wang ◽  
...  
Keyword(s):  
Bond Activation ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Bond Functionalization ◽  
Aliphatic Ketones ◽  
Site Selectivity ◽  
Mechanistic Investigation ◽  
Palladium Catalyzed ◽  
Metal Catalyzed ◽  
Site Selective

Transition metal-catalyzed selective C–H bond functionalization enabled by transient ligands has become an extremely attractive topic due to its economical and greener characteristics. However, catalytic pathways of this reaction process on unactivated sp<sup>3</sup> carbons of reactants have not been well studied yet. Herein, detailed mechanistic investigation on Pd-catalyzed C(sp<sup>3</sup>)–H bond activation with amino acids as transient ligands has been systematically conducted. The theoretical calculations showed that higher angle distortion of C(sp2)-H bond over C(sp3)-H bond and stronger nucleophilicity of benzylic anion over its aromatic counterpart, leading to higher reactivity of corresponding C(sp<sup>3</sup>)–H bonds; the angle strain of the directing rings of key intermediates determines the site-selectivity of aliphatic ketone substrates; replacement of glycine with β-alanine as the transient ligand can decrease the angle tension of the directing rings. Synthetic experiments have confirmed that β-alanine is indeed a more efficient transient ligand for arylation of β-secondary carbons of linear aliphatic ketones than its glycine counterpart.<br><br>

scholarly journals Computational study on palladium-catalyzed alkenylation of remote δ-C(sp3)–H bonds with alkynes: a new understanding of mechanistic insight and origins of site-selectivity

RSC Advances ◽  
2018 ◽  
Vol 8 (53) ◽  
pp. 30186-30190 ◽  
Author(s):  
Hui-Min Yan ◽  
Ye Tian ◽  
Niu Li ◽  
Rong Chang ◽  
Zhu-Xia Zhang ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Computational Study ◽  
Mechanistic Insight ◽  
Site Selectivity ◽  
Palladium Catalyzed

Palladium-catalyzed alkenylation of δ-C(sp3)–H bonds with alkynes was conducted by DFT calculations, showing that the dimeric Pd2(OAc)4 mechanism reproduces experimental observations well.

Theoretical and experimental studies of palladium-catalyzed site-selective C(sp3)−H bond functionalization enabled by transient ligands

2017 ◽  
Author(s):  
Haibo Ge ◽  
Lei Pan ◽  
Piaoping Tang ◽  
Ke Yang ◽  
Mian Wang ◽  
...  
Keyword(s):  
Bond Activation ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Bond Functionalization ◽  
Aliphatic Ketones ◽  
Site Selectivity ◽  
Mechanistic Investigation ◽  
Palladium Catalyzed ◽  
Metal Catalyzed ◽  
Site Selective

Transition metal-catalyzed selective C–H bond functionalization enabled by transient ligands has become an extremely attractive topic due to its economical and greener characteristics. However, catalytic pathways of this reaction process on unactivated sp<sup>3</sup> carbons of reactants have not been well studied yet. Herein, detailed mechanistic investigation on Pd-catalyzed C(sp<sup>3</sup>)–H bond activation with amino acids as transient ligands has been systematically conducted. The theoretical calculations showed that higher angle distortion of C(sp2)-H bond over C(sp3)-H bond and stronger nucleophilicity of benzylic anion over its aromatic counterpart, leading to higher reactivity of corresponding C(sp<sup>3</sup>)–H bonds; the angle strain of the directing rings of key intermediates determines the site-selectivity of aliphatic ketone substrates; replacement of glycine with β-alanine as the transient ligand can decrease the angle tension of the directing rings. Synthetic experiments have confirmed that β-alanine is indeed a more efficient transient ligand for arylation of β-secondary carbons of linear aliphatic ketones than its glycine counterpart.<br><br>

scholarly journals A Palladium-Catalyzed Oxa-(4+4)-Cycloaddition Strategy Towards Oxazocine Scaffolds

Synlett ◽  
2021 ◽  
Author(s):  
Julian Garrec ◽  
Alexis Archambeau ◽  
Anaïs Scuiller ◽  
Xueyang Liu ◽  
Marie Cordier
Keyword(s):  
Dft Calculations ◽  
Palladium Catalyzed

AbstractA Pd-catalyzed oxa-(4+4)-cycloaddition between 1-azadienes and (2-hydroxymethyl)allyl carbonates is described. Aurone-derived azadienes furnished polycyclic 1,5-oxazocines in good yields. Interestingly, linear azadienes have also been involved and yielded monocyclic heterocycles with complete regioselectivity. DFT calculations were carried out to gain insight on this observation.

Non-directed highly para-selective C-H functionalization of TIPS-protected phenols promoted by a proton shuttle

2021 ◽  
Author(s):  
Jingyao Geng ◽  
Zhang Fang ◽  
Guangliang Tu ◽  
Yingsheng Zhao
Keyword(s):  
Bioactive Molecules ◽  
Protecting Group ◽  
Mechanism Study ◽  
Phenol Derivatives ◽  
Site Selectivity ◽  
Palladium Catalyzed ◽  
Direct Functionalization ◽  
Poor Site ◽  
Site Selective ◽  
First Time

Abstract Palladium-catalyzed non-directed C-H functionalization provides an efficient approach for direct functionalization of arenes, but it usually suffers from poor site selectivity, limiting its wide application. Herein, it is reported for the first time that the proton shuttle of 3,5-dimethyladamantane-1-carboxylic acid (1-DMAdCO2H) can affect the site selectivity during the C-H activation step in palladium-catalyzed non-directed C-H functionalization, leading to highly para-selective C-H olefination of TIPS-protected phenols. This transformation displayed good generality in realizing various other para-selective C-H functionalization reactions such as hydroxylation, halogenation, and allylation reactions. A wide variety of phenol derivatives including bioactive molecules of triclosan, thymol, and propofol, were compatible substrates, leading to the corresponding para-selective products in moderate to good yields. A preliminary mechanism study revealed that the spatial repulsion factor between proton shuttle and bulky protecting group resulted in the selective C-H activation at the less sterically hindered para-position. This new model non-directed para-selective C-H functionalization can provide a straightforward route for remote site-selective C-H activations.

scholarly journals Mechanistic investigation into phenol oxidation by IBX elucidated by DFT calculations

2020 ◽  
Vol 18 (6) ◽  
pp. 1117-1129 ◽  
Author(s):  
Amritpal Kaur ◽  
Alireza Ariafard
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Density Functional ◽  
Phenol Oxidation ◽  
Hypervalent Iodine ◽  
Functional Theory ◽  
Mechanistic Investigation ◽  
Oxidation Of Phenols ◽  
Double Oxidation

Density functional theory (DFT) at the SMD/M06-2X/def2-TZVP//SMD/M06-2X/LANL2DZ(d),6-31G(d) level was used to explore the regioselective double oxidation of phenols by a hypervalent iodine(v) reagent (IBX) to give o-quinones.

Mechanism and origins of stereo- and enantioselectivities of palladium-catalyzed hydroamination of racemic internal allenes via dynamic kinetic resolution: a computational study

2020 ◽  
Vol 7 (12) ◽  
pp. 1502-1511 ◽  
Author(s):  
Zhenzhen Wu ◽  
Mei Zhang ◽  
Yu Shi ◽  
Genping Huang
Keyword(s):  
Dft Calculations ◽  
Kinetic Resolution ◽  
Computational Study ◽  
Dynamic Kinetic Resolution ◽  
Palladium Catalyzed

DFT calculations were performed to investigate the Pd-catalyzed hydroamination of racemic internal allenes with pyrazoles.

Palladium-catalyzed directing group assisted and regioselectivity reversed cyclocarbonylation of arylallenes with 2-iodoanilines

2021 ◽  
Author(s):  
Jian-Shu Wang ◽  
Lingyun Yao ◽  
Jun Ying ◽  
Xiaoling Luo ◽  
Xiao-Feng Wu
Keyword(s):  
Dft Calculations ◽  
Palladium Catalyzed ◽  
Directing Group

A palladium-catalyzed regioselective cyclocarbonylation of N-(2-pyridyl)sulfonyl (N-SO2Py)-2-iodoanilines with allenes was developed. The regioselectivity of arylallenes was reversed. Control experiments and DFT calculations were performed to understand the reaction details.

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