Theoretical study of [3 + 3] annulation reaction of bromoenal with β-tetralone catalysed by N-heterocyclic carbene DOI
Zhiyi Song, Zhiqiang Zhang, Yan Li

et al.

Molecular Physics, Journal Year: 2024, Volume and Issue: unknown

Published: June 3, 2024

N-heterocyclic carbenes (NHCs) are effective organocatalysts, which widely used in various cycloaddition reactions. Among them, the [3 + 3] reaction type can be for synthesis of six-membered ring, is also one most important methods formation carbon–carbon bonds organic chemistry. In this paper, a possible pathway stereoselective bromoenal and β-tetralone have been investigated at M06-2X/6–31G(d,p)/IEFPCM(THF) level. Our suggested mechanism includes binding NHC to bromoenal, 1,2-proton transfer, debromination, 1,3-proton shift, Michael addition, protonation, deprotonation cyclisation, regeneration. The stereochemistry determined by addition step, favourable generates R-configurational dihydropyranone. Furthermore, through use global reactivity indexes (GRIs), we able demonstrate that nucleophilicity increased NHC. mechanistic insights gained work should helpful rational design potential catalysts analogous

Language: Английский

Highly Regio-selective Hydration of Ynamides under Catalyst-Free Conditions DOI
Peng Bao, Han Xiao,

Qiuwen Li

et al.

Organic & Biomolecular Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

The highly regio-selective hydration of ynamides under catalyst-free conditions has been demonstrated for easily accessing α-amidoketones in 51-99% yields. excellent regio-selectivity is believed to be controlled by the amide group, which just opposite that observed Brønsted acid-mediated ynamides. This approach convenient, easy operate, and exhibits good functionality tolerance.

Language: Английский

Citations

0
Nickel-Catalyzed Cross-Coupling Reaction of Aryl Bromides/Nitriles with Imidazolium Salts Involving Inert C–N Bond Cleavage DOI
Zhou Jin,

Yanhao Yang,

Zhichang He

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(21), P. 4520 - 4525

Published: May 16, 2024

We herein present a nickel-catalyzed cross-coupling reaction of aryl halides and nitriles with imidazolium salts. A series 2-arylated imidazoles could be obtained in moderate to good yields through inert C-N bond cleavage. The salt this acts as both coupling partner

Language: Английский

Citations

1
Mechanisms and Stereoselectivities in the NHC-Catalyzed [4 + 2] Annulation of 2-Bromoenal and 6-Methyluracil-5-carbaldehyde DOI
Yan Li, Mingchao Zhang, Zhiqiang Zhang

et al.

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(18), P. 12997 - 13008

Published: Aug. 29, 2023

To disclose the reaction mechanism and selectivity in NHC-catalyzed of 2-bromoenal 6-methyluracil-5-carbaldehyde, a systematic computational study has been performed. According to DFT computations, catalytic cycle is divided into eight elementary steps: nucleophilic attack NHC on 2-bromoenal, 1,2-proton transfer, C–Br bond dissociation, 1,3-proton addition [2 + 2] cycloaddition, decarboxylation. The Bronsted acid DABCO·H+ plays crucial role proton transfer decarboxylation steps. 6-methyluracil-5-carbaldehyde determines both chemoselectivity stereoselectivity, leading R-configured carbocycle-fused uracil, agreement with experimental results. NCI analysis indicates that CH···N, CH···π, LP···π interactions should be key factor for determining stereoselectivity. ELF shows main promoting dissociation. mechanistic insights obtained present work may guide rational design potential catalysts.

Language: Английский

Citations

3
Theoretical study of [3 + 3] annulation reaction of bromoenal with β-tetralone catalysed by N-heterocyclic carbene DOI
Zhiyi Song, Zhiqiang Zhang, Yan Li

et al.

Molecular Physics, Journal Year: 2024, Volume and Issue: unknown

Published: June 3, 2024

N-heterocyclic carbenes (NHCs) are effective organocatalysts, which widely used in various cycloaddition reactions. Among them, the [3 + 3] reaction type can be for synthesis of six-membered ring, is also one most important methods formation carbon–carbon bonds organic chemistry. In this paper, a possible pathway stereoselective bromoenal and β-tetralone have been investigated at M06-2X/6–31G(d,p)/IEFPCM(THF) level. Our suggested mechanism includes binding NHC to bromoenal, 1,2-proton transfer, debromination, 1,3-proton shift, Michael addition, protonation, deprotonation cyclisation, regeneration. The stereochemistry determined by addition step, favourable generates R-configurational dihydropyranone. Furthermore, through use global reactivity indexes (GRIs), we able demonstrate that nucleophilicity increased NHC. mechanistic insights gained work should helpful rational design potential catalysts analogous

Language: Английский

Citations

0