Site-Selective Copper–N-Heterocyclic Carbene-Catalyzed C(sp2)–C(sp) Cross-Coupling of Aryl Thianthrenium Salts DOI
Jin Zhang, Hangsheng Yang, Li Sun

и другие.

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Март 23, 2025

This work demonstrates Cu–NHC (NHC = N-heterocyclic carbene) catalyzed alkynylation of aryl thianthrenium salts via thiazol-2-ylidene ligands, achieving a Pd-free Sonogashira coupling with broad substrate compatibility and functional group tolerance. Late-stage pharmaceutical rare alkynylative C–H functionalization/ring-opening pathways are enabled. Thiazol-2-ylidenes, featuring "half-umbrella"-shaped geometry, exhibit superior catalytic performance over traditional imidazol-2-ylidenes, underscoring their unique ligand efficacy. catalysis enables the use as versatile electrophiles for diverse cross-couplings under mild conditions.

Язык: Английский

α-Carbonyl sulfoxonium ylides in transition metal-catalyzed C–H activation: a safe carbene precursor and a weak directing group DOI
Anurag Singh, Shreemoyee Kumar, Chandra M. R. Volla

и другие.

Organic & Biomolecular Chemistry, Год журнала: 2022, Номер 21(5), С. 879 - 909

Опубликована: Дек. 6, 2022

Transition metal-catalyzed cross-coupling of sp2 C-H bonds with diazo compounds via carbene migratory insertion represents an efficient strategy for the construction C-C and C-heteroatom in organic synthesis. Despite popularity as coupling partners activation, they pose serious safety stability issues due to potential exothermic reactions linked release N2 gas. However, compared compounds, sulfoxonium ylides are generally crystalline solids, more stable, widely used industrial scales, easier/safer prepare. Therefore, recent years have witnessed upsurge employing α-carbonyl alternative surrogate transition activation. Unlike contain inherent serve a partner well weak directing group. This review will summarize progress made both categories reactions.

Язык: Английский

Процитировано

21

(NH4)2S2O8 promoted tandem radical cyclization of quinazolin-4(3H)-ones with oxamic acids for the construction of fused quinazolinones under metal-free conditions DOI
Shenyuan Gao, Menglu Cai, Gang Xu

и другие.

Organic & Biomolecular Chemistry, Год журнала: 2024, Номер 22(11), С. 2241 - 2251

Опубликована: Янв. 1, 2024

A novel cascade radical addition/cyclization reaction of non-activated olefins and oxamic acids has been proposed.

Язык: Английский

Процитировано

5

Selective Synthesis of Fused Tricyclic [1,3]oxazino[3,4‐a]indolone and Dihydropyrimido [1,6‐a]indolone via Rh(III)‐catalyzed [3+3] or [4+2] C−H Annulation DOI
Junyu Chen,

Tianshuo Zhong,

Xiangyun Zheng

и другие.

Advanced Synthesis & Catalysis, Год журнала: 2020, Номер 363(2), С. 446 - 452

Опубликована: Дек. 2, 2020

Abstract A formation of fused tricyclic [1,3]oxazino[3,4‐ a ]indol‐1‐ones and dihydropyrimido[1,6‐ ]indol‐1(2 H )‐ones via Rh(III)‐catalyzed [3+3] or [4+2] annulation N ‐methoxy‐1 ‐indole‐1‐carboxamides with sulfoxonium ylides has been developed. These selective reactions were carried out by switching the additives notable features this protocol low catalyst loading broad substrate scope providing corresponding products in up to 99% yields. magnified image

Язык: Английский

Процитировано

31

Rhodium‐Catalyzed Synthesis of Isoquinolino[1,2‐b]Quinazolines via C−H Annulation in Biomass‐Derived γ‐Valerolactone DOI
Liang Wang,

Kuan‐chang Jiang,

Nana Zhang

и другие.

Asian Journal of Organic Chemistry, Год журнала: 2021, Номер 10(7), С. 1671 - 1674

Опубликована: Апрель 15, 2021

Abstract A rhodium‐catalyzed synthesis of isoquinolino[1,2‐ b ]quinazolines via C−H annulation using vinylene carbonate as an oxidizing acetylene surrogate in biomass‐derived γ ‐valerolactone (GVL) has been developed. The reactions proceeded smoothly to give the corresponding products moderate good yields without any external oxidant and base. This protocol can also be applied for 5,6‐dihydro‐8 H ‐isoquinolino[1,2‐ ]quinazolin‐8‐ones.

Язык: Английский

Процитировано

27

Synthesis of Pyrazolo[1,2‐a]cinnolines via Rhodium(III)‐Catalyzed [4+2] Annulation Reactions of Pyrazolidinones with Sulfoxonium Ylides DOI

Shulei Hu,

Xu Han,

Xiong Xie

и другие.

Advanced Synthesis & Catalysis, Год журнала: 2021, Номер 363(13), С. 3311 - 3317

Опубликована: Май 8, 2021

Abstract A method to synthesize pyrazolo[1,2‐a]cinnolines via rhodium(III)‐catalyzed C−H activation of pyrazolidinones and subsequent [4+2] annulation sulfoxonium ylides was developed. 5‐Substituted or 5,10‐disubstituted could be obtained by slightly adjusting the reaction conditions. Gram‐scale synthesis practical transformations proved practicability this method. The mechanism proposed in article on basis preliminary mechanistic results previous reports. This features simplified operation, metal‐oxidant free, readily available reactants. magnified image

Язык: Английский

Процитировано

25

Rhodium(iii)-catalyzed C–H activation/annulation of N-iminopyridinium ylides with alkynes and diazo compounds DOI
Xiang Li, Ruihong Zhang,

Yaoting Qi

и другие.

Organic Chemistry Frontiers, Год журнала: 2021, Номер 8(6), С. 1190 - 1196

Опубликована: Янв. 1, 2021

Rh(iii)-Catalyzed C–H activation/annulation of N-iminopyridinium ylides with alkynes and diazo compounds has been realized for the synthesis isoquinolones isocoumarins.

Язык: Английский

Процитировано

24

NHPI/O2‐Mediated Electrochemical Intermolecular Cyclization/Dehydrogenation for the Construction of Polycyclic Quinazolinones DOI
Lei Liu,

Zhenhui Xu,

Jie Lin

и другие.

Advanced Synthesis & Catalysis, Год журнала: 2023, Номер 365(13), С. 2248 - 2254

Опубликована: Май 27, 2023

Abstract Herein, an eco‐friendly and atom‐economical electrochemical methodology with isatins 1,2,3,4‐tetrahydroisoquinolines through NHPI/O 2 ‐mediated intermolecular oxidation/annulation is disclosed, leading to a variety of polycyclic quinazolinones in 46–82% yields. This oxidative cyclization proceeded transition metal‐ strong oxidant‐free conditions generated H CO as byproducts. Additionally, late‐stage functionalization broad substrate scope demonstrated the synthetic usefulness this protocol.

Язык: Английский

Процитировано

11

Regioselective [3+2]‐Spiroannulation and [4+n]‐Annulation Approaches through Activation of C−H Bond Facilitated by Ru(II) as Catalyst: Role of Solvent Selectivity DOI
Rahul Dev Mandal, Anindita Sarkar, Dwaipayan Das

и другие.

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер 366(8), С. 1863 - 1876

Опубликована: Фев. 21, 2024

Abstract Ru(II)‐catalyzed and solvent‐switched [3+2]‐spiroannulation [4+n] (n=1, 2, 3) annulations of 2‐aryl quinazolinone or 2‐aryl‐2,3‐dihydrophthalazine‐1,4‐diones with ynones alkynyl alcohol 1,3‐diynes under mild reaction conditions have been analyzed. These reactions take place in the presence appropriate solvent features a redox‐neutral pathway. Ynone serves as an ‘atypical one‐carbon unit’ [4+1] annulation generates tetrasubstituted carbon center bearing diverse heterocycles through [3+2] strategies. Post transformations synthesized spiro‐products augments potential developed methodology.

Язык: Английский

Процитировано

4

Co(III)-Catalyzed Regioselective Benzannulation of Substituted Pyridones with 1,6-Diynes via Dual C-H Bond Activation DOI
Suresh Kumar Yadav, Masilamani Jeganmohan

Chemical Communications, Год журнала: 2024, Номер 60(63), С. 8296 - 8299

Опубликована: Янв. 1, 2024

A Co(III)-catalyzed site-selective C5 and C6 benzannulation of substituted pyridones with 1,6-diynes

Язык: Английский

Процитировано

4

TBHP‐Mediated Oxidative Decarboxylative Cyclization in Water: Direct and Sustainable Access to Anti‐malarial Polycyclic Fused Quinazolinones and Rutaecarpine DOI
Nanjun Chen, Fei Xia, Yifan Zhao

и другие.

Chinese Journal of Chemistry, Год журнала: 2020, Номер 38(11), С. 1239 - 1244

Опубликована: Май 17, 2020

Summary of main observation and conclusion Polycyclic fused quinazolinones with anti‐malarial activity were synthesized through tert ‐butyl hydroperoxide (TBHP)‐mediated oxidative decarboxylative cyclization between commercially available isatins cyclic amines in one step. The reaction proceeds smoothly water without additional transition‐metal catalyst, acid base. newly products evaluated to exhibit moderate good against chloroquine drug‐sensitive Plasmodium falciparum 3D7 strain. Additionally, this method also provides direct approach Rutaecarpine yield.

Язык: Английский

Процитировано

27