Stereodivergent Synthesis of Tertiary Fluoride-Tethered Allenes via Copper and Palladium Dual Catalysis

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(19), P. 7285 - 7291

Published: May 10, 2021

Herein we describe a protocol for the unprecedented stereodivergent synthesis of tertiary fluoride-tethered allenes bearing stereogenic center and axis via Cu/Pd synergistic catalysis. A broad scope conjugated enynes are coupled with various α-fluoroesters in high yields diastereoselectivities generally >99% ee. In addition, four stereoisomers allene products ensure precise access to corresponding fluorinated hydrofurans novel axial-to-central chirality transfer process.

Language: Английский

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Stereoselective Synthesis of Cyclobutanes by Contraction of Pyrrolidines

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(45), P. 18864 - 18870

Published: Nov. 8, 2021

Here we report a contractive synthesis of multisubstituted cyclobutanes containing multiple stereocenters from readily accessible pyrrolidines using iodonitrene chemistry. Mediated by nitrogen extrusion process, the stereospecific involves radical pathway. Unprecedented unsymmetrical spirocyclobutanes were prepared successfully, and concise, formal cytotoxic natural product piperarborenine B is reported.

Language: Английский

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Progress in organocatalysis with hypervalent iodine catalysts

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(18), P. 8102 - 8139

Published: Jan. 1, 2022

Hypervalent iodine compounds as environmentally friendly and relatively inexpensive reagents have properties similar to transition metals. They are employed alternatives metal catalysts in organic synthesis mild, nontoxic, selective recyclable catalytic reagents. Formation of C-N, C-O, C-S, C-F C-C bonds can be seamlessly accomplished by hypervalent catalysed oxidative functionalisations. The aim this review is highlight recent developments the utilisation iodine(III) iodine(V) a wide range including chiral for stereoselective synthesis. Polymer-, magnetic nanoparticle- framework-supported also described.

Language: Английский

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Regio‐ and Enantioselective Intermolecular Aminofluorination of Alkenes via Iodine(I)/Iodine(III) Catalysis**

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(32)

Published: May 18, 2022

The regio- and enantio-selective, intermolecular vicinal fluoroamination of α-trifluoromethyl styrenes has been achieved by enantioselective I

Language: Английский

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A Chiral Pentafluorinated Isopropyl Group via Iodine(I)/(III) Catalysis

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(12), P. 6430 - 6434

Published: Jan. 15, 2021

An I(I)/(III) catalysis strategy to construct an enantioenriched fluorinated isostere of the

Language: Английский

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Organoiodine-Catalyzed Enantioselective Intermolecular Oxyamination of Alkenes

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(4), P. 1745 - 1751

Published: Jan. 22, 2021

Metal-free, catalytic enantioselective intermolecular oxyamination of alkenes is realized by use organoiodine(I/III) chemistry. The protocol applicable toward aryl- and alkyl-substituted with high enantioselectivity electronically controlled regioselectivity. oxyaminated products can be easily deprotected in one step to reveal free amino alcohols yields without loss enantioselectivity. A key our success the discovery a virtually unexplored chemical entity, N-(fluorosulfonyl)carbamate, as bifunctional N,O-nucleophile.

Language: Английский

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Stereocontrolled Synthesis of Fluorinated Isochromans via Iodine(I)/Iodine(III) Catalysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(30)

Published: May 10, 2022

The success of saturated, fluorinated heterocycles in contemporary drug discovery provides a stimulus for creative endeavor main group catalysis. Motivated by the ubiquity isochromans across bioactive small molecule spectrum, prominence anomeric effect regulating conformation, and metabolic lability benzylic position, iodine(I)/iodine(III) catalysis has been leveraged stereocontrolled generation selectively analogs. To augment current arsenal fluorocyclization reactions involving carboxylic acid derivatives, reaction readily accessible 2-vinyl benzaldehydes is disclosed (up to >95 : 05 d.r. 97 03 e.r.). Key stereoelectronic interactions manifest themselves X-ray crystal structures products, thereby validating [CH

Language: Английский

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Catalyst-Substrate Helical Character Matching Determines the Enantioselectivity in the Ishihara-Type Iodoarenes Catalyzed Asymmetric Kita-Dearomative Spirolactonization

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(13), P. 7301 - 7312

Published: March 20, 2023

Catalyst design has traditionally focused on rigid structural elements to prevent conformational flexibility. Ishihara's elegant of conformationally flexible C2-symmetric iodoarenes, a new class privileged organocatalysts, for the catalytic asymmetric dearomatization (CADA) naphthols is notable exception. Despite widespread use Ishihara catalysts CADAs, reaction mechanism remains subject debate, and mode induction not been well established. Here, we report an in-depth computational investigation three possible mechanisms in literature. Our results, however, reveal that this best rationalized by fourth called "proton-transfer-coupled-dearomatization (PTCD)", which predicted be strongly favored over other competing pathways. The PTCD consistent with control experiment further validated applying it rationalize enantioselectivities. Oxidation I(I) catalyst active I(III) species induces defined helical chiral environment delicate balance between flexibility rigidity. A match/mismatch effect substrate's shape transition states was observed. match allows adapt its conformation maximize attractive noncovalent interactions, including I(III)···O halogen bond, N-H···O hydrogen π···π stacking, stabilize state. stereochemical model capable rationalizing variation enantioselectivities developed. present study enriches our understanding how achieve high stereoinduction may serve as inspiration future exploration designs.

Language: Английский

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Flow electrochemistry: a safe tool for fluorine chemistry

Chemical Science, Journal Year: 2021, Volume and Issue: 12(26), P. 9053 - 9059

Published: Jan. 1, 2021

A scalable, efficient and safe electrochemical fluorination protocol is conferred. broad range of iodine(iii) mediated transformations were performed in high yields without exposure to toxic HF.

Language: Английский

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Electrophilic Fluorination of Alkenes via Bora‐Wagner–Meerwein Rearrangement. Access to β‐Difluoroalkyl Boronates

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(50), P. 26327 - 26331

Published: Oct. 8, 2021

The electrophilic fluorination of geminal alkyl substituted vinyl-Bmida derivatives proceeds via bora-Wagner-Meerwein rearrangement. According to DFT modelling studies this rearrangement occurs with a low activation barrier bora-cyclopropane shaped TS. Bmida group has larger migration aptitude than the moiety in Wagner-Meerwein presented reactions.

Language: Английский

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