Cobalt‐Catalyzed Annulation of o‐Phenylenediamines and Internal Alkynes: Efficient Synthesis of Quinoxaline Derivatives DOI
Rui Zhao,

Ling Wu,

S.‐F. CHEN

и другие.

European Journal of Organic Chemistry, Год журнала: 2023, Номер 27(3)

Опубликована: Ноя. 6, 2023

Abstract A cobalt‐catalyzed annulation of o ‐phenylenediamines and internal alkynes for the synthesis quinoxalines is developed. This method provides a variety in good to high yields under simple mild reaction conditions with molecular O 2 as terminal oxidant. Preliminary mechanistic studies show that novel mechanism involved current reaction, which different from previous reported dicarbonyl compound via oxidation alkyne.

Язык: Английский

Recent Strategies in the Nucleophilic Dearomatization of Pyridines, Quinolines, and Isoquinolines DOI Creative Commons
Marcos Escolano, Daniel Gaviña, G. Alzuet

и другие.

Chemical Reviews, Год журнала: 2024, Номер 124(3), С. 1122 - 1246

Опубликована: Янв. 2, 2024

Dearomatization reactions have become fundamental chemical transformations in organic synthesis since they allow for the generation of three-dimensional complexity from two-dimensional precursors, bridging arene feedstocks with alicyclic structures. When those processes are applied to pyridines, quinolines, and isoquinolines, partially or fully saturated nitrogen heterocycles formed, which among most significant structural components pharmaceuticals natural products. The inherent challenge lies low reactivity heteroaromatic substrates, makes dearomatization process thermodynamically unfavorable. Usually, connecting event irreversible formation a strong C–C, C–H, C–heteroatom bond compensates energy required disrupt aromaticity. This aromaticity breakup normally results 1,2- 1,4-functionalization heterocycle. Moreover, combination these subsequent tandem stepwise protocols allows multiple heterocycle functionalizations, giving access complex molecular skeletons. aim this review, covers period 2016 2022, is update state art nucleophilic dearomatizations showing extraordinary ability dearomative methodology indicating their limitations future trends.

Язык: Английский

Процитировано

61

B2pin2-Mediated Cascade Cyclization/Aromatization Reaction: Facial Access to Functionalized Indolizines DOI
Xiaoning Li,

Zunsheng Chen,

Weiming Chen

и другие.

Organic Letters, Год журнала: 2022, Номер 24(40), С. 7372 - 7377

Опубликована: Сен. 29, 2022

Herein, a B2pin2-mediated radical cascade cyclization/aromatization reaction of enaminone with pyridine is described. This strategy provides practical way for the construction valuable functionalized indolizines under metal-, external oxidant-, and base-free conditions, which could be compatible various kinds functional groups, such as halogen, π-system, heterocycle, ferrocenyl, etc. A preliminary mechanism investigation indicated that pyridine-boryl formed in situ triggered to occur.

Язык: Английский

Процитировано

31

Copper-Catalyzed Annulation of O-Acyl Oximes with Cyclic 1,3-Diones for the Synthesis of 7,8-Dihydroindolizin-5(6H)-ones and Cyclohexanone-Fused Furans DOI
Hai‐Tao Yang,

Su-Qing Zhou,

Danmei Chen

и другие.

Organic Letters, Год журнала: 2023, Номер 25(5), С. 838 - 842

Опубликована: Янв. 27, 2023

A copper-catalyzed annulation of O-acyl oximes with cyclic 1,3-diones has been developed for the concise synthesis 7,8-dihydroindolizin-5(6H)-ones and cyclohexanone-fused furans through substituent-controlled selective radical coupling process. 2-Alkyl undergo C-C coupling, while 2-unsubstituted C-O coupling.

Язык: Английский

Процитировано

19

Synthesis of Indolizines via Tf2O-Mediated Cascade Reaction of Pyridyl-enaminones with Thiophenols/Thioalcohols DOI
Changyuan Zhang, Wei Wang,

Xuncheng Zhu

и другие.

Organic Letters, Год журнала: 2023, Номер 25(7), С. 1192 - 1197

Опубликована: Фев. 13, 2023

A cost-effective, highly regioselective and metal-free version for the synthesis of indolizine derivatives by means Tf2O-mediated cascade reaction pyridyl-enaminones thiophenols/thioalcohols under mild conditions has been reported. Diverse electron-rich could be obtained in up to 94% yield via selective 1,4-addition vinyl iminium triflate tandem cyclization/aromatization, which allowed simultaneous construction C–N C–S/and one example C–Se bonds.

Язык: Английский

Процитировано

15

Synthesis of Stable N–H Imines with a Benzo[7,8]indolizine Core and Benzo[7,8]indolizino[1,2-c]quinolines via Copper-Catalyzed Annulation of α,β-Unsaturated O-Acyl Ketoximes with Isoquinolinium N-Ylides DOI
Chun‐Bao Miao,

Xiao-Qi Qiang,

Xiaoli Xu

и другие.

Organic Letters, Год журнала: 2022, Номер 24(21), С. 3828 - 3833

Опубликована: Май 23, 2022

A copper-catalyzed annulation of α,β-unsaturated O-acyl ketoximes with isoquinolinium N-ylides has been developed for the concise synthesis stable N-H imines a benzo[7,8]indolizine core. When β-(2-bromoaryl)-α,β-unsaturated are used as starting materials, cascade cyclization occurs to afford benzo[7,8]indolizino[1,2-c]quinolines.

Язык: Английский

Процитировано

22

Copper-Catalyzed [3 + 2] Annulation of O-Acyl Oximes with 4-Sulfonamidophenols for the Synthesis of 5-Sulfonamidoindoles and 2-Amido-5-sulfonamidobenzofuran-3(2H)-ones DOI

Zi-Jun Hu,

Wei Chen,

Xinyu Lyu

и другие.

Organic Letters, Год журнала: 2024, Номер 26(20), С. 4229 - 4234

Опубликована: Май 13, 2024

A copper-catalyzed [3 + 2] annulation of

Язык: Английский

Процитировано

4

Synthesis of spiroisoxazoline oxindoles by base-promoted annulation of oxime esters and isatins DOI
Si-Wei Chen,

Xu‐Hua Hu,

Ling Wu

и другие.

Tetrahedron Letters, Год журнала: 2025, Номер 159, С. 155506 - 155506

Опубликована: Март 6, 2025

Язык: Английский

Процитировано

0

Iron-Catalyzed Double Annulation of O-Acyl Oximes with Fumaronitrile for the Synthesis of 4-Cyano-7-azaindoles DOI

Xian-Heng Ding,

Hui Li, Zhen Cui

и другие.

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Июнь 2, 2025

An iron-catalyzed double annulation of O-acyl oximes with fumaronitrile has been developed for the concise synthesis polysubstituted 4-cyano-7-azaindoles. This method enables construction two fused heterocycles in a one-step reaction using readily available starting materials under redox-neutral conditions.

Язык: Английский

Процитировано

0

Copper-catalyzed [4+2] oxidative annulation of α,β-unsaturated ketoxime acetates with ethyl trifluoropyruvate DOI
Huan Yan,

Gaochen Xu,

Meng Gu

и другие.

Chemical Communications, Год журнала: 2022, Номер 58(47), С. 6757 - 6760

Опубликована: Янв. 1, 2022

A novel route for tandem C-N/C-O formation via copper-catalyzed [4+2] oxidative annulation of α,β-unsaturated ketoxime acetates with ethyl trifluoropyruvate to synthesize valuable trifluoromethyl-containing 2H-1,3-oxazines in moderate good yields is developed. This procedure represents the first oxime derivatives activated CO bonds and provides an alternative towards functionalized 2H-1,3-oxazines.

Язык: Английский

Процитировано

11

Copper-catalyzed [3+2] annulation of O-acyl ketoximes with 2-aryl malonates for the synthesis of 3-aryl-4-pyrrolin-2-ones DOI

Xiaoqing Song,

Xiao-Qi Qiang,

Zi-Jun Hu

и другие.

Chemical Communications, Год журнала: 2023, Номер 59(35), С. 5225 - 5228

Опубликована: Янв. 1, 2023

A copper-catalyzed [3+2] annulation of O -acyl ketoximes with 2-aryl malonates for the concise synthesis 3-aryl-4-pyrrolin-2-ones has been developed.

Язык: Английский

Процитировано

6