Theoretical Study of Ni-Catalyzed C-N Radical-Radical Cross-Coupling.

J Org Chem

School of Chemistry and Chemical Engineering, and Chongqing Key Laboratory of Theoretical and Computational Chemistry , Chongqing University, Chongqing 400030 , China.

Published: March 2019


Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

A computational study was carried out to investigate the mechanism and the origin of chemoselectivity in nickel-catalyzed C-N radical-radical cross-coupling reaction. The global electrophilicity index ω° and global nucleophilicity index N° were used to quantitatively describe the electrophilic or nucleophilic character of the carbon radical, nitrogen radical, and Ni(II) complex. The calculated ω° and N° values indicate that introduction of nickel makes C-N cross-coupling to be a facile process. Detailed theoretical results show that the cross-coupling occurs through the combination of Ni(I) complex with a nitrogen-centered radical, a minimum energy crossing point to form the singlet Ni(II) complex, and radical addition of the nucleophilic carbon-centered radical lead to C-N bond formation. On the basis of the theoretical results, a generalized scheme is provided to clarify the origin of the chemoselectivity in nickel-catalyzed C-N radical-radical cross-coupling.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.joc.8b03245DOI Listing

Publication Analysis

Top Keywords

c-n radical-radical
12
radical-radical cross-coupling
12
origin chemoselectivity
8
chemoselectivity nickel-catalyzed
8
nickel-catalyzed c-n
8
niii complex
8
c-n
5
cross-coupling
5
radical
5
theoretical study
4

Similar Publications

Enantioconvergent Radical-Radical Cross-Coupling via Magnesium-Mediated Charge-Transfer Photocatalysis.

J Am Chem Soc

July 2025

State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.

Radical asymmetric reactions represent a crucial strategy in asymmetric synthesis, which is characterized by their high reaction efficiency and unique reactivity profiles. Despite significant progress in radical-based asymmetric transformations, the formation of C-N bonds using nonredox metal complexes via the inner-sphere stereocontrol mechanism remains a formidable challenge in the development of novel asymmetric catalytic strategies. This study introduces an innovative and highly efficient asymmetric photochemical bifunctional catalysis that utilizes a combination of magnesium salts and chiral PyBOX-type (pyridine-bisoxazoline) -symmetric ligands under visible light irradiation.

View Article and Find Full Text PDF

Aromatic compounds serve as key feedstocks in the chemical industry, typically undergoing functionalization or full reduction. However, partial reduction via dearomative sequences remains underexplored despite its potential to rapidly generate complex three-dimensional scaffolds and the existing dearomative strategies often require metal-mediated multistep processes or suffer from limited applicability. Herein, a photocatalytic radical cascade approach enabling dearomative difunctionalization through selective spirocyclization/imination of nonactivated arenes is reported.

View Article and Find Full Text PDF

An EnT-mediated C3-N-heteroarylation of 2-aryl quinoxalines via decarboxylative radical-radical cross-coupling (C(sp)-C(sp)) with oxime esters is presented. Upon photoactivation, the triplet energy of the photocatalyst is transferred to both reacting partners (oxime ester and 2-phenylquinoxaline). The excited oxime ester undergoes decarboxylative fragmentation to a C-centered N-heteroaryl radical and an N-centered imine radical.

View Article and Find Full Text PDF

The [1,2]-rearrangement of allylic ammonium ylides is traditionally observed as a competitive minor pathway alongside the thermally allowed [2,3]-sigmatropic rearrangement. Concerted [1,2]-rearrangements are formally forbidden, with these processes believed to proceed through homolytic C-N bond fission of the ylide, followed by radical-radical recombination. The challenges associated with developing a catalytic enantioselective [1,2]-rearrangement of allylic ammonium ylides therefore lie in biasing the reaction pathway to favor the [1,2]-reaction product, alongside controlling a stereoselective radical-radical recombination event.

View Article and Find Full Text PDF

The control of enantioselectivity in radical cation reactions presents long-standing challenges, despite a few successful examples. We introduce a novel strategy of asymmetric counteranion-directed electrocatalysis to address enantioselectivity in radical cation chemistry. This concept has been successfully demonstrated in two reactions: an asymmetric dehydrogenative indole-phenol [3+2] coupling and an atroposelective C-H/N-H dehydrogenative coupling.

View Article and Find Full Text PDF