Enantioselective Parallel Kinetic Resolution of Aziridine-Containing Quinoxalines via Chiral Phosphoric Acid Catalyzed Transfer Hydrogenation

Опубликована: Сен. 21, 2023

This manuscript describes asymmetric synthesis of novel chiral aziridinoquinoxaline scaffolds using phosphor-ic acid-catalyzed parallel kinetic and resolutions under transfer hydrogenation conditions with Hantzsch es-ters. While the achiral phosphoric acids such as BPPA were found to promote diastereoselective substrate-controlled reductions from more sterically accessible face excellent diastereoselectivities, (R)-TRIP catalyst was unique in dictating catalyst-controlled Si-face selectivity for both enantiomers starting materials. The kinet-ic resolution successfully accomplished 16 different substrates led highly enantioenriched readily separable diasteromers (S)-configuration newly formed stereocenter (32-61% yield, 64-99% ee, (S,S,R)-diastereomers 7-45% 97-99% ee (R,R,S)-diastereomers). process could be coupled ring-opening (S,S,R)-diastereomer thiophenol produce tetrahydroquinoxalines three con-tiguous stereocenters.

Язык: Английский

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Green Light Promoted Iridium(III)/Copper(I)‐Catalyzed Addition of Alkynes to Aziridinoquinoxalines Through the Intermediacy of Azomethine Ylides

Angewandte Chemie, Год журнала: 2024, Номер 136(12)

Опубликована: Янв. 25, 2024

Abstract This manuscript describes the development of alkyne addition to aziridine moiety aziridinoquinoxalines using dual Ir(III)/Cu(I) catalytic system under green light‐emitting diode (LED) photolysis (λ max =525 nm). mild method features high levels chemo‐ and regioselectivity was used generate 30 highly functionalized substituted dihydroquinoxalines in 36–98 % yield. transformation also carried asymmetrically phthalazinamine‐based chiral ligand provide 9 products 96 : 4 86 14 e.r. The experimental quantum chemical explorations this reaction suggest a mechanism that involves Ir(III)‐catalyzed triplet energy transfer followed by ring‐opening ultimately leading formation azomethine ylide intermediates. These intermediates undergo sequential protonation/copper(I) acetylide products.

Язык: Английский

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Non-classical effective methods for reduction of heteroaromatic compounds

Russian Chemical Reviews, Год журнала: 2024, Номер 93(11), С. RCR5149 - RCR5149

Опубликована: Окт. 30, 2024

The review summarizes the known data on various methods for saturation and dearomatization of heterocyclic moieties, forming diverse aromatic compounds. Since classical hydrogenation substrates with molecular hydrogen has a number fundamental drawbacks that hinder both its use at laboratory level widespread implementation in industrial production, main attention is paid to non-classical described literature over last 20–25years. ammonia-free Birch reduction, transfer hydrogenation, reduction by Hantzsch esters some other reactions involving compounds are summarized systematized. It shown such or heterocycles can cases be more efficient than procedures.<br> bibliography includes 173 references.

Язык: Английский

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Asymmetric Transfer Hydrogenation in Flow

Synfacts, Год журнала: 2023, Номер 19(11), С. 1171 - 1171

Опубликована: Окт. 14, 2023

Key words transfer hydrogenation - chiral phosphoric acid enantioselectivity

Язык: Английский

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