Recent Advances in Asymmetric Dearomatization Reactions Induced by Chiral Hypervalent Iodine Reagents

Chinese Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 43(11), P. 3784 - 3784

Published: Jan. 1, 2023

Language: Английский

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Computational Insights into the Reactivity Difference between Hypervalent Bromine(III) and Hypervalent Iodine(III) Reagent in the C−H Amination and Alkene Aziridination

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(16), P. 2737 - 2743

Published: June 9, 2023

Abstract We present herein a computational exploration into the mechanism and origin of reactivity difference between N ‐triflylimino‐λ 3 ‐iodane ‐bromane in C−H amination alkene aziridination. Our calculations revealed that preferred for involves generation free nitrene intermediate, while aziridination proceeds via concerted reaction mechanism. The superior over could be mainly ascribed to better nucleofugality bromanyl moiety, which can characterized by strength I−N Br−N bond. effect solvent polarity on as precursor will discussed.

Language: Английский

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(2 R ,2′ R )‐2,2′‐[(2‐Iodo‐1,3‐phenylene)bis(oxy)]bis[ N ‐(2,4,6‐trimethylphenyl)propanamide]

Encyclopedia of Reagents for Organic Synthesis, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 7

Published: April 18, 2024

image [1226896‐38‐3] C 30 H 35 IN 2 O 4 (MW 614.5245) InChI = 1S/C30H35IN2O4/c1‐16‐12‐18(3)27(19(4)13‐16)32‐29(34)22(7)36‐24‐10‐9‐11‐25(26(24)31)37‐23(8)30(35)33‐28‐20(5)14‐17(2)15‐21(28)6/h9‐15,22‐23H,1‐8H3,(H,32,34)(H,33,35)/t22‐,23‐/m1/s1 InChiKey ZVOKSLMZXDIXPR‐DHIUTWEWSA‐N (catalyst for oxidative coupling reactions, 1–3 the precursor of chiral organoiodine(III) reagent ) Alternative Names : ( R , )‐2‐Iodo‐1,3‐bis[1‐(mesitylcarbamoyl)ethoxy]benzene. Physical Data –116.1° c 1.0, CHCl 3 ). Solubility soluble in most organic solvents except hydrocarbons (e.g., hexane) and diethyl ether. Form Supplied white to off‐white crystal. Handling, Storage, Precautions light, air, heat sensitive. Store under inert gas a dark place at 2–10 °C. Preparation (2 ,2′ )‐2,2′‐[(2‐Iodo‐1,3‐phenylene)bis(oxy)]bis[ N ‐(2,4,6‐trimethylphenyl)propanamide], )‐ 1a can be prepared from 2‐iodoresorcinol three steps (eq 1). 4,5 The Mitsunobu reaction with (–)‐ethyl lactate affords ‐symmetric bisester. Hydrolysis followed by dichlorination thionyl chloride, diamidation via mesitylamine gives . is commercially available FUJIFILM Wako Pure Chemical Corporation, Tokyo Industry Co., Ltd.

Language: Английский

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Predicting bond dissociation energies of cyclic hypervalent halogen reagents using DFT calculations and graph attention network model

Beilstein Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 20, P. 1444 - 1452

Published: June 28, 2024

Although hypervalent iodine(III) reagents have become staples in organic chemistry, the exploration of their isoelectronic counterparts, namely bromine(III) and chlorine(III) reagents, has been relatively limited, partly due to challenges synthesizing stabilizing these compounds. In this study, we conduct a thorough examination both homolytic heterolytic bond dissociation energies (BDEs) critical for assessing chemical stability functional group transfer capability cyclic halogen compounds using density theory (DFT) analysis. A moderate linear correlation was observed between BDEs across different centers, while strong noted among centers. Furthermore, developed predictive model machine learning algorithms. The results study could aid estimating capabilities thereby facilitating development.

Language: Английский

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Computational Elucidation on the Conformational Control of Selectivity in Intramolecular Ring-Closing Metathesis vs Intermolecular Homometathesis

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(13), P. 8512 - 8521

Published: June 26, 2023

The ring-closing metathesis reaction of diene plays an important role in the construction cyclic compounds. In this research, density functional theory (DFT) calculations were conducted to elucidate mechanisms and origins selectivity homometathesis. computational results suggest that is determined by substrate conformation. For ester-tethered substrate, homometathesis more favorable, due planar structure ester facilitating conjugative effect formed E-homometathesis product. amide-tethered product only observed because steric hindrance N-substituents disfavors

Language: Английский

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Unraveling Alcohol Additive Effects on Hypervalent Iodine(III)-Catalyzed Asymmetric Phenolic Dearomatization: Ligand Substitution and Low-Barrier Hydrogen Bonds

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

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New conformationally flexible and recyclable aryl iodine catalysts from inexpensive chiral source for asymmetric oxidations

Research Square (Research Square), Journal Year: 2023, Volume and Issue: unknown

Published: April 24, 2023

Abstract Despite the remarkable advances in research field of asymmetric catalytic oxidation reactions via hypervalent iodines with simple procedures, high level efficiency and stereoselectivity over past few decades, development their highly scalable, environmentally benign, sustainable protocols under greener organocatalysis paradigm for further industrial translations remains a long-standing synthetic organic chemistry process engineering challenge. Herein, we design synthesize new library conformationally flexible recyclable aryl iodine catalysts by utilization (i) waste (chloramphenicol base) as scaffold (ii) inexpensive amino acid residue (threonine) chiral source. Our iodine(III) bearing H-bond donors tunable pocket have been successfully applied diverse robust oxidative transformations, e.g., dearomatization, spirolactonization, direct C(sp 2 )−H/C(sp 3 )−H cross-coupling, fluoridation. processes feature column-isolation-free approach, easy-handling operation, upscaling synthesis, being facilely recycled particular precipitation.

Language: Английский

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