Three-component synthesis ofN-naphthyl pyrazolesviaRh(iii)-catalyzed cascade pyrazole annulation and Satoh–Miura benzannulation

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(27), P. 4036 - 4039

Published: Jan. 1, 2023

The synthesis of N-naphthyl pyrazoles has been realized by the direct three-component reactions enaminones, aryl hydrazine hydrochlorides and internal alkynes via Rh(III) catalysis. synthetic employing simple substrates lead to simultaneous construction dual cyclic moieties, including a pyrazole ring phenyl ring, sequential formation two C-N three C-C bonds.

Language: Английский

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Three-Component Chemo-Selective Synthesis of N-(o-Alkenylaryl) Pyrazoles by Pyrazole Annulation and Rh-Catalyzed Chemo-Selective Aryl C–H Addition Cascade

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(13), P. 8619 - 8627

Published: May 31, 2023

By using readily available enaminones, aryl hydrazine hydrochlorides, and alkynes as starting materials, the chemo-selective three-component synthesis of atropisomeric N-(o-alkenylaryl) pyrazoles has been efficiently accessed with rhodium catalysis. Unlike Satoh-Miura reaction leading to alkyne-based C-H benzannulation by prior prepared N-phenyl substrates, this protocol displays unprecedented selectivity alkenylation blocking second round metal key protonation step in presence acids.

Language: Английский

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Rhodium‐Catalyzed Dual C−H Activation for Regioselective Triple Annulation of Enaminones: Access to Polycyclic Naphthopyran Derivatives

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(11), P. 1770 - 1776

Published: March 21, 2023

Abstract Rh‐catalyzed C−H activation of arenes for oxidative annulations with alkynes stands out as a protocol polycyclic scaffolds. This perspective drives us to disclose herein rhodium catalyzed regioselective triple annulation enaminones hydroxyl‐alkynoates via double functionalization naphtho‐pyran Secondary coordination OH in alkynoate dictated the regioselectivity. Initial lactonization occurred chemoselectively on enamine part carbo rhodation followed by reductive elimination. was scalable and has shown high functionality tolerance. KIE studies were done get insight mechanism, some downstream transformations achieved show synthetic potential method.

Language: Английский

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Rh(II)-Catalyzed Synthesis of N-Aryl 2-pyridone Using 2-Oxypyridine and Diazonaphthoquinone Via 1,6-Benzoyl Migratory Rearrangement

Organic Letters, Journal Year: 2023, Volume and Issue: 25(16), P. 2873 - 2877

Published: April 13, 2023

A Rh(II)-catalyzed simple and efficient synthesis of N-arylated 2-pyridone derivatives is described using 2-oxypyridine diazonaphthoquinone as coupling partners. The reaction proceeds through the insertion nitrogen atom derivative into quinoid carbene subsequent 1,6-benzoyl migratory rearrangement. broadened with sufficient scope has potential to offer axially chiral under suitable asymmetric conditions.

Language: Английский

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Pd-catalyzed regioselective rollover dual C–H annulation cascade: facile approach to phenanthrene derivatives

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(64), P. 9714 - 9717

Published: Jan. 1, 2023

A Pd-catalyzed rollover cascade dual C–H annulation of aryl phenols with alkynols for producing phenanthrene scaffolds in a regioselective manner was developed. Necessary control, KIE and deuterium experiments were conducted to determine the reaction mechanism.

Language: Английский

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Copper-Catalyzed Regioselective Imidation of 2-Pyridones

Organic Letters, Journal Year: 2024, Volume and Issue: 26(15), P. 3048 - 3053

Published: April 5, 2024

We demonstrate a ligand- and glovebox-free regioselective direct C(3)–H imidation of 2-pyridones also benzylic-type bearing methyl substituent employing Cu(OAc)2·H2O as the catalyst N-fluorobenzenesulfonimide (NFSI) an imidating reagent. A broad range imidated 2-pyridone derivatives is made up to excellent yields. The present strategy operates well on gram scale, ensuing product can be readily subjected mono- bis-desulfonylation reactions.

Language: Английский

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Pd(II)-Catalyzed Oxidative Naphthylation of 2-Pyridone through N–H/C–H Activation Using Diarylacetylene as an Uncommon Arylating Agent

Organic Letters, Journal Year: 2023, Volume and Issue: 25(11), P. 1952 - 1957

Published: March 10, 2023

A Pd(II)-catalyzed straightforward oxidative naphthylation of unmasked 2-pyridone derivatives is described using a twofold internal alkyne as coupling partner. The reaction proceeds through N–H/C–H activation to provide polyarylated N-naphthyl 2-pyridones. An unusual annulation at the arene C–H bond diarylalkyne leads formation 2-pyridones, where 2-pyridone-attached phenyl ring naphthyl polyaryl-substituted. Mechanistic studies and DFT calculations suggest plausible mechanism based on activation. were studied explore encouraging photophysical properties.

Language: Английский

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Palladium-Catalyzed Weak Chelation-Assisted Site-Selective C–H Arylation of N-Aryl Pyridones via 2-fold C–H Activation

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(9), P. 6564 - 6574

Published: April 17, 2024

Palladium-catalyzed weak chelation-assisted oxidative cross-dehydrogenative coupling of arenes has been accomplished. The use medicinally important pyridones as the intrinsic directing group, regioselectivity, 2-fold C–H activation, and late-stage modification bioactive compounds are practical features.

Language: Английский

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Transition Metal‐Catalyzed Dual C−H Activation/Annulation Reactions Involving Internal Alkynes

The Chemical Record, Journal Year: 2024, Volume and Issue: 24(7)

Published: July 1, 2024

Recently, transition metal-catalyzed ortho-C-H bond activation/annulations involving two internal alkyne molecules have been extensively used to synthesize highly substituted polycyclic aromatic scaffolds. Such reactions emerged as a powerful atom and step-economical strategy for the assembly of multifunctional bioactive molecules. In this context, we focused on recent achievements dual C-H activation/annulations, well functionalization diaryl/alkyl alkynes.

Language: Английский

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Conjugated Olefin Enabled Rollover Cyclometallation of Distant C‐H Bonds: Regioselective Annulation of o‐Alkenyl Phenols with Alkynes

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(70)

Published: Oct. 11, 2023

Although challenging, the distant C-H functionalization with precision is quite rewarding and has long been intriguing. Tailoring an appropriate template accomplishes job but prerequisite sets limitation. We herein unveil our discovery of annulation alkynes on to two (from directing group) bonds through rollover cyclometallation assisted by conjugated C=C bond. The follows a concomitant cyclization rare triple functionalization. totally regioselective array unsymmetrical alkynes, taking leverage extended conjugation or tertiary hydroxyl co-ordination. mechanism supported control experiments, KIE & labelling studies Mass spectrometry.

Language: Английский

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