Synthesis of Benzoisochromene Derivatives via C–H Activation-Initiated Cascade Formal [4+2] and [2+4] Annulation of Aryl Enaminone with Vinyl-1,3-dioxolan-2-one

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Март 19, 2025

Cascade annulation reactions can assemble structurally intricate polycyclic molecules from simple starting materials with enhanced efficiency and minimized production of waste. Presented herein is a concise effective synthesis benzoisochromene derivatives based on C-H activation-initiated cascade formal [4+2]/[2+4] aryl enaminone vinyl-1,3-dioxolan-2-one. In constructing the six-membered carbocycle, acted as C4 synthon while vinyl-1,3-dioxolan-2-one C2 synthon. O-heterocycle, other hand, former latter C3O1 To our knowledge, this first simultaneous construction both carbocycle an O-heterocycle via concurrent C-H/C-N/C-O bond cleavage C-C/C-C/C-O formation. general, novel protocol features use readily obtainable substrates broad scope, excellent atom- step-economy, intriguing reaction pathway, valuable products.

Язык: Английский

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Highly Dispersed Single-Phase Ni₂P Nanoparticles on N,P-Codoped Porous Carbon for Efficient Synthesis of N-Heterocycles

ACS Sustainable Chemistry & Engineering, Год журнала: 2019, Номер 8(1), С. 267 - 277

Опубликована: Дек. 3, 2019

Aerobic oxidative cross-dehydrogenative coupling represents one of the most straightforward and atom-economic methods for construction C–C C–X (X = N, O, S, or P) bonds, especially when environmentally friendly air is used as oxidant. Herein, we report development an inexpensive, stable, highly dispersed ultrafine Ni2P nanoparticles with narrow size distribution supported on N,P-codoped biomass-derived porous carbon. The as-prepared catalyst active stable synthesis pharmaceutically important N-heterocycles, including quinazolines, quinazolinones, imidazoles, through a wide range alcohols diamines 2-aminobenzamides using atmospheric sole oxidant under mild reaction conditions. This work provides new method to access which operationally simple, widely applicable various (or 2-aminobenzamides), capable gram-scale synthesis, highlighting its practical potential. Mechanistic studies reveal that proceeds in cascade manner, hydrogen acceptor significantly boosts overall efficiency.

Язык: Английский

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Recent Achievements in the Rhodium‐Catalyzed Concise Construction of Medium N‐Heterocycles, Azepines and Azocines

Advanced Synthesis & Catalysis, Год журнала: 2020, Номер 362(24), С. 5576 - 5600

Опубликована: Ноя. 13, 2020

Abstract Medium N‐heterocycles, azepines and azocines, serve as important skeletons that occurred widely in natural products, however, due to the lack of efficient synthetic methodologies, their application potential biologically active molecules, pharmaceuticals agrochemicals remained be explored. In this context, rhodium catalysis field featured good reactivity functional group tolerance, with readily available starting materials, enabled rapid access azocines. Delightfully, great achievements concise construction these 7 8‐membered N‐heterocycles under have been made, which mainly included cycloisomerization unsaturated C−X bonds (which might also combine ring‐opening strategy on strained rings), metal carbenoid or nitrene insertion involved transformations direct C−H activation reactions. Considering performance catalyst synthesis herein, we summarized recent results field, wish give further insight inspired more encouraging methodologies new drug discovery based N‐heterocycles. magnified image

Язык: Английский

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Ketone-derived 2,3-dihydroquinazolinones inN-heteroarene C–H alkylationviaC–C bond scission under oxidative metal catalysis

Chemical Communications, Год журнала: 2022, Номер 58(95), С. 13202 - 13205

Опубликована: Янв. 1, 2022

A silver-catalysed oxidative sp2 C-H alkylation of N-heteroarenes with ketone-derived 2,3-dihydroquinazolinones at room temperature is developed. The combination a metal catalyst and perdisulfate oxidant promotes the rarely explored thermal activation pre-aromatic 2,3-dihydroquinazolinone to generate an alkyl radical, supported by mechanistic studies. In addition broad scope, good functionality tolerance, late stage functionalization APIs, synthesis novel Papaverine analogue, utilization N-heteroarene bond ketone as non-trivial radical source represents salient feature this method.

Язык: Английский

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Rh(iii)-catalyzed selective mono- and dual-functionalization/cyclization of 1-aryl-5-aminopyrazoles with iodonium ylides

Chemical Communications, Год журнала: 2023, Номер 60(4), С. 432 - 435

Опубликована: Дек. 5, 2023

Highly functionalized benzodiazepine skeletons were efficiently synthesized via a Rh( iii )-catalyzed selective mono- and dual-C–H bond functionalization/cyclization reaction between readily available 1-aryl-5-aminopyrazoles iodonium ylides under.

Язык: Английский

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Directing Group Assisted Unsymmetrical Multiple Functionalization of Arene C−H Bonds

The Chemical Record, Год журнала: 2020, Номер 20(9), С. 1017 - 1042

Опубликована: Авг. 11, 2020

Abstract Multiple C−H bond functionalizations promptly install diverse groups on the molecular framework and consequently fabricate complex entities. This review briefly surveys conceptual development of directing group assisted unsymmetrical multiple functionalization arene C(sp 2 )−H bonds, which is exceedingly appealing highly important.

Язык: Английский

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Synthesis of CF₃-Azafluorenes through the Cascade Reaction of 2H-Imidazoles with CF₃-Ynones

Organic Letters, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 25, 2024

A concise synthesis of trifluoromethyl (CF

Язык: Английский

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Synthesis of Indenopyrazole Frameworks via Cascade C–H Functionalization/[3 + 2] Dipolar Cycloaddition/Aromatization Rearrangement Reactions

Organic Letters, Год журнала: 2020, Номер 22(18), С. 7152 - 7157

Опубликована: Авг. 28, 2020

The redox-neutral Ir(III)- or Ru(II)-catalyzed C–H couplings of azomethine imines with α,α-difluoromethylene alkynes have been realized, leading to the efficient synthesis indenopyrazole frameworks via a tandem functionalization/[3 + 2] dipolar cycloaddition/ring-opening aromatization rearrangement process, in which generated fluoroallene species was involved as dipolarophile selective β-F elimination process. Subsequent biological evaluation revealed that these synthesized indenopyrazoles could serve interesting cytotoxic agents for further development.

Язык: Английский

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Weak coordinated nitrogen functionality enabled regioselective C–H alkynylationviaPd(ii)/mono-N-protected amino acid catalysis

Chemical Communications, Год журнала: 2020, Номер 56(76), С. 11255 - 11258

Опубликована: Янв. 1, 2020

By using mono-N-protected amino acid (MPAA) ligand under Pd(ii) catalysis, regioselective C–H alkynylation of weak coordinated nitrogen functionalities was developed with great efficiency, proceedingvia5, 6 and 7-membered palladacycle intermediates.

Язык: Английский

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Metal-Free Atom-Economical Synthesis of Tetra-Substituted Imidazoles via Flavin-Iodine Catalyzed Aerobic Cross-Dehydrogenative Coupling of Amidines and Chalcones

The Journal of Organic Chemistry, Год журнала: 2022, Номер 87(15), С. 10372 - 10376

Опубликована: Июль 15, 2022

Herein, we demonstrated the oxidative cross-dehydrogenative coupling between amidines and chalcones catalyzed by flavin iodine. The riboflavin-iodine catalytic system played multiple roles in substrate- O2-activation, enabling facile atom-economical synthesis of tetra-substituted imidazoles good yields (60-87%). This metal-free reaction consumed only 1 equiv molecular oxygen generated 2 environmentally benign H2O as byproduct.

Язык: Английский

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