One‐Pot Synthesis of Fused N,O‐Heterocycles through Rh(III)‐Catalyzed Cascade Reactions of Aromatic/Vinylic N‐Alkoxy‐ Amides with 4‐Hydroxy‐2‐Alkynoates

Advanced Synthesis & Catalysis, Год журнала: 2018, Номер 360(14), С. 2613 - 2620

Опубликована: Март 31, 2018

Abstract A highly efficient and regioselective synthesis of furo[3,4‐ c ]isoquinoline‐1,5(3 H ,4 )‐diones b ]pyridine‐2,5(1 ,7 via Rh(III)‐catalyzed one‐pot cascade reactions aromatic/vinylic N ‐alkoxyamides with 4‐hydroxy‐2‐alkynoates is presented. Mechanistically, the formation title compounds triggered by a inert C( sp 2 )−H bond activation amide substrate followed its [4+2] annulation lactonization 4‐hydroxy‐2‐alkynoate featuring an oxidizing partially traceless directing group. To best our knowledge, this first example in which both furan‐2(5 )‐one pyridin‐2(1 scaffolds are constructed one pot under set reaction conditions. Compared literature methods, notable features new protocol include facile bis‐heterocyclic from readily available acyclic substrates, broad scope good tolerance wide range functional groups, excellent regioselectivity high efficiency. magnified image

Язык: Английский

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Regioselective Synthesis of 2-Alkenylindoles and 2-Alkenylindole-3-carboxylates through the Cascade Reactions of N-Nitrosoanilines with Propargyl Alcohols

The Journal of Organic Chemistry, Год журнала: 2018, Номер 83(15), С. 8509 - 8521

Опубликована: Июнь 14, 2018

In this paper, a novel and efficient synthesis of 2-alkenylindoles 2-alkenylindole-3-carboxylates via the cascade reactions N-nitrosoanilines with propargyl alcohols is presented. Mechanistically, formation title compounds triggered by Rh(III)-catalyzed C(sp2)-H alkenylation N-nitrosoaniline alcohol followed simultaneous intramolecular amination/cyclization, NO extrusion, dehydration. With method, variety diversely substituted 2-alkenylindole derivatives were prepared in good efficiency exclusive site-selectivity. To best our knowledge, first example which indoyl alkenyl units are formed sequentially one pot from halide-free substrates through redox neutral C-H bond activation. addition, utility products thus obtained was remarkably showcased their facile transformations into synthetically biologically significant such as 2-acylindole, benzocarbazole, indoloquinoline, pyridoindolone, cyclopentaindolone, indenoindolone.

Язык: Английский

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Rhodium-Catalyzed Selective Oxidative (Spiro)annulation of 2-Arylindoles by Using Benzoquinone as a C2 or C1 Synthon

Organic Letters, Год журнала: 2019, Номер 21(16), С. 6437 - 6441

Опубликована: Авг. 6, 2019

Rhodium-catalyzed substrate-tunable oxidative annulation and spiroannulation reactions of 2-arylindoles with benzoquinone leading to 9H-dibenzo[a,c]carbazol-3-ols new spirocyclic products are reported. Intriguingly, 2-aryl-substituted indoles, could act as a C2 synthon afford dibenzo[a,c]carbazoles. On the contrary, when 2-aryl-3-substituted indoles were used, switched C1 furnish compounds. In addition, further transformations obtained demonstrate synthetic utility present protocol.

Язык: Английский

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Selective Synthesis of 3‐(α‐Fluorovinyl)indoles and 3‐Acylindoles via the Cascade Reactions of 1‐Phenylpyrazolidinones with α,α‐Difluoromethylene Alkynes

Advanced Synthesis & Catalysis, Год журнала: 2021, Номер 363(14), С. 3600 - 3606

Опубликована: Июнь 10, 2021

Abstract Presented herein is a selective synthesis of 3‐(α‐fluorovinyl)indoles and 3‐acylindoles via the coupling 1‐phenylpyrazolidinones with α,α‐difluoromethylene alkynes. Mechanistically, formation resulted from cascade process including Rh(III)‐catalyzed ortho ‐C−H bond cleavage, regioselective triple insertion, pyrazolidinone ring‐opening, indole ring‐formation HF elimination. Interestingly, when this reaction was carried out in CH 3 OH/H 2 O instead CN, situ formed readily undergo hydration to afford 3‐acylindole derivatives. This protocol features controllable selectivity, simultaneous both heterocyclic scaffold monofluoroalkenyl moiety, atom‐economy, substrate diversity, good functional group tolerance redox‐neutral conditions. Anticancer screening selected products against two human cancer cell lines demonstrated their potential as lead compounds for drug development. magnified image

Язык: Английский

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Transition‐Metal‐Catalyzed C−H Bond Functionalization of Arenes/Heteroarenes via Tandem C−H Activation and Subsequent Carbene Migratory Insertion Strategy

The Chemical Record, Год журнала: 2021, Номер 21(12), С. 4088 - 4122

Опубликована: Окт. 14, 2021

Abstract The past decade has witnessed tremendous developments in transition‐metal‐catalyzed C−H bond activation and subsequent carbene migratory insertion reactions, thus assisting the construction of diverse arene/heteroarene scaffolds. Various transition‐metal catalysts serve this purpose provide efficient pathways for an easy access to substituted heterocycles. A brief introduction metal‐carbenes been provided along with key mechanistic underlying coupling reactions. review is a concise knowledge about directing group‐assisted varied arenes/heteroarenes acceptor‐acceptor/donor‐acceptor diazo compounds. also highlights synthesis various carbocycles fused heterocycles through pathways, via C−C, C−N C−O forming mechanism usually involves process, followed by leading coupling.

Язык: Английский

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Rhodium(III)-Catalyzed Dehydrogenative Annulation and Spirocyclization of 2-Arylindoles and 2-(1H-Pyrazol-1-yl)-1H-indoles with Maleimides: A Facile Access to Isogranulatimide Alkaloid Analogues

The Journal of Organic Chemistry, Год журнала: 2021, Номер 86(3), С. 2328 - 2338

Опубликована: Янв. 12, 2021

A Rh(III)-catalyzed dehydrogenative annulation and spirocyclization of 2-arylindoles 2-(1H-pyrazol-1-yl)-1H-indole with maleimides is described. The cascade protocol provided highly functionalized benzo[a]pyrrolo[3,4-c]carbazole-1,3(2H,8H)-diones spiro[isoindolo[2,1-a]indole-6,3′-pyrrolidine]-2′,5′-diones in good to excellent. developed reaction methodology exhibited broad substrate scope functional group tolerance operationally simple scalable. Photophysical properties the annulated products were investigated. product showed high absorption emission values a large red-shift as compared that 2-phenylindole.

Язык: Английский

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The solvent-controlled Rh(iii)-catalyzed switchable [4+2] annulation of 2-arylIndoles with iodonium ylides

Chemical Communications, Год журнала: 2022, Номер 58(41), С. 6140 - 6143

Опубликована: Янв. 1, 2022

Highly selective and switchable [4+2] annulations of 2-arylindoles with iodonium ylides were achieved by performing solvent-controlled Rh(III)-catalyzed C-H activations. When using DCM as a solvent, the functionalization selectively delivered indolo[2,1-a]isoquinoline derivatives. In contrast, same catalytic system polar HFIP solvent predominately provided benzo[a]carbazole moieties.

Язык: Английский

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Rh(iii)-catalyzed C–H activation/annulation of N-carbamoylindoles with CF₃-imidoyl sulfoxonium ylides for the divergent synthesis of trifluoromethyl-substituted (dihydro)pyrimidoindolones

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(15), С. 3843 - 3848

Опубликована: Янв. 1, 2023

We have developed a Rh( iii )-catalyzed C–H activation/chemodivergent annulation of N -carbamoylindoles with TFISYs, allowing facile access to variety trifluoromethyl-substituted (dihydro)pyrimidoindolones high efficiency. Solvents play critical role in the selectivity reaction.

Язык: Английский

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Rh(III)-Catalyzed C–H Activation of Benzoylacetonitriles and Tandem Cyclization with Diazo Compounds to Substituted Benzo[de]chromenes

Organic Letters, Год журнала: 2018, Номер 20(7), С. 1720 - 1724

Опубликована: Март 22, 2018

Rh (III)-catalyzed C–H activation of benzoylacetonitriles in coupling with diazo compounds was developed to synthesize diversified substituted benzo[de]chromenes via a formal (4 + 2) cycloaddition compound and subsequent tandem another compound. Intriguingly, synthesis their decarboxylation products could be realized by controlling the reaction conditions. These reactions have broad range substrates, moderate good yields, high regioselectivity.

Язык: Английский

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Synthesis of maleimide fused benzocarbazoles and imidazo[1,2-a]pyridines via rhodium(iii)-catalyzed [4 + 2] oxidative cycloaddition

Organic Chemistry Frontiers, Год журнала: 2020, Номер 7(22), С. 3698 - 3704

Опубликована: Янв. 1, 2020

In this paper, an efficient and sustainable synthesis of maleimide-fused benzocarbazoles/imidazo[1,2-a]pyridines from the reaction 2-arylindoles/2-arylimidazo[1,2-a]pyridines with maleimides through oxidative [4 + 2] annulation is presented.

Язык: Английский

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