Unraveling Alcohol Additive Effects on Hypervalent Iodine(III)-Catalyzed Asymmetric Phenolic Dearomatization: Ligand Substitution and Low-Barrier Hydrogen Bonds DOI
Hanliang Zheng, Cai Liu,

Xiaoyu Lai

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 15(1), P. 370 - 380

Published: Dec. 18, 2024

Despite the widespread use of hexafluoropropanol (HFIP) as a "magic" solvent or additive in organic synthesis, its fundamental mechanisms lag far behind. This study presents mechanistic insights into puzzling alcohol effects observed Ishihara's conformationally flexible C2-symmetric iodoarene-catalyzed asymmetric phenolic dearomatization through density functional theory calculations. The results reveal that due to "booster effect" fluorinated alcohols, HFIP assembles trimeric hydrogen bond cluster displaces ligand from active iodine(III) catalyst and forms low-barrier with substrate, which significantly enhances oxidizing power center, thus facilitating electron-deficient phenols. Conversely, methanol is found promote electron-rich phenols via formally similar yet distinct mechanism, highlighting unique role an additive. gained this investigation advance our molecular-level understanding synergistic interactions between catalysts additives, potentially guiding design catalytic systems exploit these for broader applications.

Language: Английский

Halogen Bonding and Rearrangements in Complexes of N-Chlorosuccinimide with Halides DOI Creative Commons

Maison Hardin,

Mat­thias Zeller, Sergiy V. Rosokha

et al.

Molecules, Journal Year: 2025, Volume and Issue: 30(3), P. 639 - 639

Published: Jan. 31, 2025

The role of halogen bonding (HaB) in the reactions N-chlorosuccinimide (SimCl), a versatile reagent organic synthesis, was investigated through experimental and computational analyses its interactions with halides. SimCl Br− or I− resulted crystallization HaB complexes chloride N-iodosuccinimide (SimI) N-bromosuccinimide (SimBr). Computational analysis revealed that rearrangements, which occurred even at −73 °C, were facilitated by bonding. dissociation SimCl∙Y− (Y = I Br) into Sim− + ClY pair (followed rotation re-binding interhalogen molecules) bypassed formation high-energy Cl+ drastically (about tenfold) reduced energy N–Cl bond. Furthermore, while individual is higher (and weaker) compared to SimI SimBr, N-Cl bond requires less than SimBr SimI. facile cleavage such bonds explains high reactivity effectiveness as halogenating agent.

Language: Английский

Citations

0
Computational Design of Bidentate HypervalentIodine Catalysts in Halogen Bond‐MediatedOrganocatalysis DOI Creative Commons

James A O’Brien,

Nika Melnyk, R. Lee

et al.

ChemPhysChem, Journal Year: 2024, Volume and Issue: 25(22)

Published: July 8, 2024

In recent years, halogen bond-based organocatalysis has garnered significant attention as an alternative to hydrogen-based catalysis, capturing considerable interest within the scientific community. This transition witnessed evolution of catalytic scaffolds from monodentate bidentate architectures, and monovalent hypervalent species. this DFT-based study, we explored a iodine(III)-based system that already undergone experimental validation. Additionally, explore various functionalisations (-CF

Language: Английский

Citations

1
Unraveling Alcohol Additive Effects on Hypervalent Iodine(III)-Catalyzed Asymmetric Phenolic Dearomatization: Ligand Substitution and Low-Barrier Hydrogen Bonds DOI
Hanliang Zheng, Cai Liu,

Xiaoyu Lai

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 15(1), P. 370 - 380

Published: Dec. 18, 2024

Despite the widespread use of hexafluoropropanol (HFIP) as a "magic" solvent or additive in organic synthesis, its fundamental mechanisms lag far behind. This study presents mechanistic insights into puzzling alcohol effects observed Ishihara's conformationally flexible C2-symmetric iodoarene-catalyzed asymmetric phenolic dearomatization through density functional theory calculations. The results reveal that due to "booster effect" fluorinated alcohols, HFIP assembles trimeric hydrogen bond cluster displaces ligand from active iodine(III) catalyst and forms low-barrier with substrate, which significantly enhances oxidizing power center, thus facilitating electron-deficient phenols. Conversely, methanol is found promote electron-rich phenols via formally similar yet distinct mechanism, highlighting unique role an additive. gained this investigation advance our molecular-level understanding synergistic interactions between catalysts additives, potentially guiding design catalytic systems exploit these for broader applications.

Language: Английский

Citations

1