Functional Group Evaluation Kit for Digitalization of Information on the Functional Group Compatibility and Chemoselectivity of Organic Reactions

Bulletin of the Chemical Society of Japan, Journal Year: 2023, Volume and Issue: 96(5), P. 465 - 474

Published: April 18, 2023

Abstract Digitalization of information on organic reactions is essential for developing next-generation syntheses with artificial intelligence and machine-learning (ML) methods. In this regard, reliable functional group compatibility chemoselectivity critical understanding the applicability reactions. Herein, we report digitalization using a evaluation (FGE) kit that allows accurate rapid assessment given Our 26 FGE compounds were used to evaluate 4 types (i.e., cross-coupling, proline-catalyzed aldol, condensation, ketimine synthesis reactions). As result, obtained valuable new model retrosynthetic analysis tools deeper these

Language: Английский

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Recent Progress on Catalytic Addition Reactions toN-Unsubstituted Imines

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(12), P. 6924 - 6951

Published: May 27, 2020

Catalytic addition reactions to N-unsubstituted (N-unprotected) imines can provide a more straightforward synthesis of amines. This direct process eliminates the unnecessary protecting-group manipulations that are required with N-substituted (N-protected) and contribute development green chemistry. Although their use has been limited due difficulties associated nature imines, recently developed catalytic methods enable as electrophiles in various reactions. To facilitate an understanding state art synthetic methodologies, herein we review recent progress on imines. We begin overview chemistry followed by summary categorized according reaction type. hope this will help stimulate further greener syntheses nitrogen-containing compounds.

Language: Английский

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Remote C–H Amination and Alkylation of Camphor at C8 through Hydrogen-Atom Abstraction

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(11), P. 7850 - 7857

Published: March 6, 2024

Camphor continues to serve as a versatile chiral building block for chemical synthesis. We have developed novel method functionalize the camphor skeleton at C8 using an intramolecular hydrogen atom abstraction. The key advance involves use of camphor-derived aminonitrile, which is converted corresponding nitrogen-centered radical under photoredox conditions effect 1,5-hydrogen transfer C8. resulting carbon-centered was utilized in C–H amination access topologically complex proline derivatives. Furthermore, total synthesis several sesquiterpenoids accomplished by engaging generated alkylation reactions.

Language: Английский

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Ammonia surrogates in the synthesis of primary amines

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(35), P. 7036 - 7051

Published: Jan. 1, 2023

This review provides a comprehensive summary of the utilization ammonia replacements in synthesizing protected and free primary amines, encompassing both traditional reagents latest developments.

Language: Английский

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Direct Benzylic C–H Functionalization with Fluorenones under Visible-Light Irradiation

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(4), P. 2612 - 2620

Published: Feb. 1, 2023

An external photocatalyst-free benzylic C-H functionalization with fluorenones under visible-light irradiation has been achieved. This transformation provides an efficient synthetic approach to 9-benzylated fluorenols in ≤91% yield 100% atom economy mild conditions. Spectroscopic studies suggest that a reductive quenching of photoexcited toluene derivatives generates ketyl radicals and benzyl radicals, which undergo cross-coupling afford the desired fluorenols.

Language: Английский

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Sc(OTf)₃-Catalyzed C–C Bond Cleavage of Unactivated Acylazaarenes with 1,2-Diamines to Afford Azaarenes and Imidazoles

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 25, 2025

We report a method for cleaving the C(O)-sp2C bonds of unactivated acylazaarenes via benzimidazoline intermediates using mild redox neutral catalytic system involving scandium triflate. This avoids need preactivation or transition metal catalysts, enabling efficient C-C bond cleavage in broad range substrates, including 2-acylimidazoles, 2-acylpyridines, 2-acylpyrole, and even nonchelating 3-acylindole, which direct has not been previously achieved.

Language: Английский

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Catalytic Enantioselective Strecker Reaction of Isatin-Derived N-Unsubstituted Ketimines

Organic Letters, Journal Year: 2021, Volume and Issue: 23(12), P. 4553 - 4558

Published: May 24, 2021

A catalytic enantioselective Strecker reaction of isatin-derived N-unsubstituted ketimines directly afforded the N-unprotected α-aminonitriles with a tetrasubstituted carbon stereocenter in up to 99% ee without requiring protection/deprotection steps. One-pot reactions from parent carbonyl compounds were also realized comparable yields and enantioselectivities. Direct transformations α-aminonitrile products streamlined synthesis unnatural amino acid derivatives achieved shortest one-pot stereoselective routes biologically active compound reported date.

Language: Английский

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Chiral Primary Amine Catalyzed Enantioselective Tandem Reactions Based on Heyns Rearrangement: Synthesis of α-Tertiary Amino Ketones

Organic Letters, Journal Year: 2022, Volume and Issue: 24(10), P. 2069 - 2074

Published: March 9, 2022

Herein, we disclose a new catalytic asymmetric tandem reaction based on the Heyns rearrangement for synthesis of chiral α-amino ketones with readily available substrates. The is different from in that were obtained without shift carbonyl group. key to success using primary amine as catalyst by mimicking glucosamine-6-phosphate synthase catalyzing efficient organisms.

Language: Английский

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Organocatalytic Direct Enantioselective Hydrophosphonylation of N-Unsubstituted Ketimines for the Synthesis of α-Aminophosphonates

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(5), P. 3158 - 3163

Published: Feb. 17, 2023

We report an organocatalyzed direct enantioselective hydrophosphonylation of N-unsubstituted ketimines that affords N-unprotected α-tetrasubstituted α-aminophosphonates without protection/deprotection steps. The reaction is suitable for isatin-derived and trifluoromethyl ketimines, affording products in high yields with excellent enantioselectivity. Applications the a proposed transition state model are also described.

Language: Английский

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Selective and Functional-Group-Tolerant Photoalkylation of Imines by Energy-Transfer Photocatalysis

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(21), P. 15209 - 15217

Published: Oct. 24, 2023

Basic amines show broad bioactivity and remain a promising source of new medicines. The direct photoalkylation imines offers strategy for complex amines. However, the lack efficient imine photoreactivity hinders this reaction remains fundamental limitation in organic photochemistry. We report an that provides primary directly without protecting or leaving groups. transformation effects C-H addition across N-H under energy-transfer photocatalysis by ketone. Our method is distinguished from organometallic, metal-catalyzed, photoredox approaches to alkylation its groups scope, which includes unactivated alkanes, protic substrates, basic amines, heterocycles, ketone imines. highlight scope through condensation two pharmaceutical ketones, providing succinctly. mechanistic analysis supports three-step process, involving hydrogen-atom transfer triplet excited state, intersystem crossing, radical recombination, with photocatalytic enhancement energy transfer. further are more photoreactive than N-substituted imines, distinction partially explained sterics side reactions. To fully explain distinction, we introduce thermodynamic parameter excited-state affinity, highly effective at predicting

Language: Английский

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