Results 21 to 30 of about 337 (160)

Rapid Assembly of Spiroisoxazolidines by [4 + 1] Dearomative Spiroannulation of α‑Bromo-β-naphthol and Nitroolefin

, 2023
A novel [4 + 1] dearomative spiroannulation of α-halo-β-naphthol and nitroolefin has been developed for the direct construction of various spiroisoxazolidines in high chemo- and diastereoselectivity.
Jingjing Liu, Lu Bai, Mengyao Li (2634310), Xinjun Luan, Jingjing Liu (305549), Lu Bai (343118), Mian Qi, Mengyao Li, Mian Qi (1343880), Xinjun Luan (1614730)   +9 more
core   +1 more source

Gold(I)-Catalyzed Ring-Expanding Spiroannulation of Cyclopropenones with Enynes

, 2016
The gold­(I)-catalyzed ring-expanding spiroannulation of cyclopropenones with enynes is reported here. A molecule of water is incorporated into the products during the spiroannulation to afford spirocyclic cyclopentenones containing an alcohol ...
Takanori Matsuda (1830835), Yusuke Sakurai (1830832)   +1 more
core   +1 more source

Dearomatizing Spiroannulation Reagents: Direct Access to Spirocycles from Indoles and Dihalides [PDF]

Organic Letters, 2018
Unfunctionalized indoles can be directly converted into 3,3'-spirocyclic indolenines and indolines upon reaction with electrophilic dihalides in the presence of t-BuOK/BEt3. This double C-C bond forming reaction, which simultaneously generates a quaternary spirocyclic center, typically proceeds in high yield and has good functional group tolerance.
Liddon, John T R, Rossi-Ashton, James A, Taylor, Richard J K, Unsworth, William P   +3 more
openaire   +4 more sources

Concise Synthesis of Spirocyclic Dihydrophthalazines through Spiroannulation Reactions of Aryl Azomethine Imines with Cyclic Diazo Compounds

, 2022
Spiroannulation reactions are fundamental and invaluable for the synthesis of spirocyclic compounds. Presented herein are novel cascade reactions of aryl azomethine imines with cyclic diazo compounds leading to the formation of spirocyclic ...
Xinying Zhang (808783), Qiuhui Zhu (12231776), Xuesen Fan (808785), Xinyuan Cai (13104889), Xia Song (594494)   +4 more
core   +1 more source

Strategies Toward Accessing Enantioenriched (Hetero)Benzo‐Fused 5‐ and 6‐ Membered Rings via Intermolecular Carbometalation

Angewandte Chemie International Edition, Volume 65, Issue 23, 1 June 2026.
The use of transition‐metal catalysts and design of chiral ligands have allowed chemists to access highly functionalized benzofused 5‐ and 6‐ membered rings in high yield and enantioselectivity. A common strategy used relies on an intermolecular carbometalation across alkynes and olefins, usually followed by a subsequent intramolecular carbometalation.
Clara Jans, Armaan Grewal, Xavier Abel‐Snape, Mark Lautens   +3 more
wiley   +1 more source

One‐Pot Cascade Synthesis of Isoquinolinone‐Fused Quinoxalines Through Sequential Rh(III)/Pd(II) Catalysis

Advanced Synthesis &Catalysis, Volume 367, Issue 20, October 29, 2025.
A new one‐pot, dual catalytic strategy for the synthesis of polycyclic isoquinolinone‐fused quinoxalines from commercially available N‐(2‐acetamidophenyl)benzamides and 1,3‐diynes is reported. This transformation proceeds via Rh(III)/Pd(II)‐mediated sequential NH/CH activation/annulation. Detailed mechanistic studies elucidate the reaction pathway. A
Wei‐Jung Chiu, Indrajeet J. Barve, Hung‐Sheng Hsieh, Chung‐Ming Sun   +3 more
wiley   +1 more source

Electrophilic aryl spiroannulation induced by diaryliodonium salts: efficient synthesis of [5,5]-spiro lactone-lactam scaffolds from α-cyanocarboxylates

Green Synthesis and Catalysis
Spirocyclic architectures represent one of the privileged three-dimensional scaffolds in pharmaceutical chemistry and drug discovery, while the new-skeletal synthesis of spiromolecules from simple starting materials remains a challenging task.
Zhiyuan Bao, Yifei Li, Ruitong Zhang, Zhengsen Yu, Chao Chen   +4 more
doaj   +1 more source

Asymmetric Synthesis of Highly Substituted Spiro[2H‐pyrrole‐2,3‐Succinimide] Derivatives by Copper‐Catalyzed Post‐Ugi Reactions

Advanced Synthesis &Catalysis, Volume 367, Issue 13, July 23, 2025.
Abstract Herein we present a novel one‐pot methodology for the synthesis of enantioenriched 2H‐pyrrolespirosuccinimides by copper‐catalyzed reactions on Ugi adducts derived from enantiopure α‐alkylbenzyl amines through a chirality transfer process. We have proposed a mechanism, supported by density functional theory (DFT) calculations, where a hydrogen
Javier Gómez‐Ayuso, Israel Carreira‐Barral, Roberto Quesada, María García‐Valverde   +3 more
wiley   +1 more source

Participation of β‑Ketothioamides in N‑Heterocyclic Carbene-Catalyzed [3 + 3] Spiroannulation: Asymmetric Synthesis of Functionalized Spiro-piperidinone Derivatives

, 2018
An N-heterocyclic carbene-catalyzed asymmetric [3 + 3] spiroannulation of β-ketothioamide was successfully developed. β-Ketothioamides exhibit an unusual reactivity to undergo a previously challenging lactamization reaction, and the desired spiro ...
Jia-Lu Zhang (3860683), Chang-Yin Tan (6033467), Huan-Xin Zhang (6033470), Jin-Yu Liu (2075794), Hong Lu (58784), Peng-Fei Xu (38571), Hong-Yu Li (3041163)   +6 more
core   +2 more sources

Heterogeneously Catalyzed Cascade Oxidative Coupling/Dearomative Spirocyclization of Diarylamines: Facile Access to Spiroacridines

Advanced Synthesis &Catalysis, Volume 367, Issue 9, May 6, 2025.
Abstract Spirocyclic compounds, particularly spirocyclohexadienones, are important in pharmaceuticals due to their biological activity. In this study, we develop a catalytic cascade oxidative spirocyclization of diarylamines for the rapid access to highly functionalized spirocyclohexadienones. Using commercially available recyclable heterogeneous metal
Kenji Matsumoto, Naho Sato, Yoshinori Kobayashi, Kanako Date, Yasuko Okamoto, Touya Kariya, Tsukasa Hirokane, Masahiro Yoshida   +7 more
wiley   +1 more source