Reaction condition-dependent divergent synthesis of spirooxindoles and bisoxindoles DOI

Guo‐Shu Chen,

Yu‐Bo Fang, Zhi Ren

et al.

Organic Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 8(14), P. 3820 - 3828

Published: Jan. 1, 2021

DABCO-catalyzed divergent transformations of isatin-derived MBH carbonates leading to either spirocyclopentene oxindoles, spirocyclopentadiene 2-oxindoles or bisoxindoles are described.

Language: Английский

NHC-catalysed retro-aldol/aldol cascade reaction enabling solvent-controlled stereodivergent synthesis of spirooxindoles DOI
Hai‐Jun Leng, Qian Zhao, Qing Mao

et al.

Chinese Chemical Letters, Journal Year: 2021, Volume and Issue: 32(8), P. 2567 - 2571

Published: March 7, 2021

Language: Английский

Citations

31
Use of (E,E)-Dienoic Acids as Switchable (E,E)- and (Z,E)-Dienyl Anion Surrogates via Ligand-Controlled Palladium Catalysis DOI

Shun‐Zhong Tan,

Peng Chen, Lei Zhu

et al.

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(49), P. 22689 - 22697

Published: Dec. 5, 2022

Carboxylic acids are not readily applied as carbon-based nucleophiles due to their intrinsic acidic group. Here, we demonstrate that free (E,E)-2,4-dienoic form electron-neutral and highest occupied molecular orbital-raised η2-complexes with Pd(0) undergo Friedel–Crafts-type additions imines exclusive α-regioselectivity, giving formal dienylated products after decarboxylation. Unusual switchable (E,E)- (Z,E)-selectivity, along excellent enantioselectivity, is achieved via ligand-controlled outer-sphere or inner-sphere reaction modes, respectively, which well supported by comprehensive density functional theory calculation studies. An unprecedented reductive Mannich between (E,E)-dienoic also developed furnish enantioenriched β-amino acid derivatives.

Language: Английский

Citations

22
Ir-Catalyzed Asymmetric Cascade Allylation/Spiroketalization Reaction for Stereoselective Synthesis of Oxazoline-Spiroketals DOI
Hui Yan, Xusheng Shao, Xiaoyong Xu

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(2), P. 325 - 330

Published: Jan. 6, 2023

An asymmetric cascade allylation/spiroketalization reaction between 2-(1-hydroxyallyl)phenols and 5-methyleneoxazolines is accomplished by using a chiral Ir(I) catalyst derived from commercially available iridium precursor the Carreira ligand. This protocol furnishes class of structurally novel unique oxazoline-spiroketals in up to 86% yield, >99% ee >20:1 dr. Moreover, control experiments reveal that 4,4-disubstitution on necessary avoid aromatization for spiroketalization occur. On basis this, plausible mechanism illustrated.

Language: Английский

Citations

11
Palladium-Catalyzed Divergent Synthesis from o-Sulfonamido Trifluoroacetophenones and 2-En-4-ynyl Carbonates DOI

Meng-Qi Gan,

Jian‐Xiang Zhu,

Zhichao Chen

et al.

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 15, 2025

Here we present a palladium-catalyzed divergent transformative reaction between o-sulfonamido trifluoroacetophenones and 2-en-4-ynyl carbonates. A spectrum of enantioenriched 2,5-dihydrofuran-fused tetrahydroquinolines bearing either (Z)- or (E)-exocyclic double bond are constructed with moderate to high enantioselectivity from 5-aryl-substituted carbonates by tuning palladium sources, while analogous 2,3-dihydrofuran-fused products furnished using 5-alkyl-substituted ones.

Language: Английский

Citations

0
Direct Enantioselective Allylic Alkylation of α-Amino Esters to Quaternary Glutamates via Strategic Pyridoxal Catalyst Design DOI
Zhengjun Shi, Tianhao Wu,

Longjie Huang

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: April 24, 2025

The difficulty for N-unprotected α-substituted glycinates as α-C nucleophiles originates from both competing N nucleophilic interference and steric hindrance of the α substituent, which makes direct asymmetric alkylation with Morita-Baylis-Hillman (MBH) adducts especially challenging. Given wide utilization α-quaternary chiral glutamic acid derivatives in therapeutic studies, we took advantage biomimetic carbonyl catalysis to achieve their efficient synthesis. A bifunctional centrally pyridoxal, featured an expanded catalytic cavity reduced around aldehyde group, was designed synthesized. In this work, describe novel pyridoxal enabled MBH acetates. broad range multiple modifications were produced high reactivity excellent stereocontrol.

Language: Английский

Citations

0
Photoredox/Nickel-Catalyzed Diastereoselective Allylation of Aldehydes with Morita–Baylis–Hillman Adducts DOI Creative Commons
F. Calogero, Emanuele Pinosa, Andrea Gualandi

et al.

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 8303 - 8316

Published: May 2, 2025

Language: Английский

Citations

0
Iridium/Acid Dual-Catalyzed Enantioselective Aza-ene-type Allylic Alkylation of Nitro Ketene Aminals with Racemic Allylic Alcohols DOI

Diancong Chen,

Man Zhang, Dongxu Zhang

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(2), P. 508 - 513

Published: Jan. 5, 2024

The enantioselective allylic alkylation of nitro ketene aminals with racemic alcohols was realized by iridium/acid dual catalysis. An allyl group installed on the α-position in a branched-selective manner high efficiency excellent enantioselectivities (93–99% ee). protocol applied to late-stage modification neonicotinoid insecticides, which directly furnished novel analogue good insecticidal activity against Aphis craccivora (LC50 = 6.40 mg/L). On basis control experiment, an aza-ene-type reaction mechanism proposed.

Language: Английский

Citations

3
4‐(Dimethylamino)pyridine‐Catalyzed (3+2) Annulation of Pyrazoledione‐Derived Morita–Baylis–Hillman Carbonates with 2‐Arylideneindane‐1,3‐Diones: An Access to Dispirocyclic Compounds DOI

Jianning Liao,

Jiaqing Xu,

Yongjun Wu

et al.

Advanced Synthesis & Catalysis, Journal Year: 2022, Volume and Issue: 364(6), P. 1074 - 1079

Published: Jan. 28, 2022

Abstract A 4‐(dimethylamino)pyridine‐catalyzed (3+2) annulation of pyrazoledione‐derived Morita–Baylis–Hillman (MBH) carbonates with 2‐arylideneindane‐1,3‐diones has been developed to afford various multifunctional spiropyrazole derivatives in 16–99% yields 3:2–>20:1 diastereoselectivities. As a type Lewis‐base receptor, the MBH will function as key substrate organocatalyzed reactions for diverse syntheses pyrazolinone‐containing dispirocyclic compounds. magnified image

Language: Английский

Citations

16
Bifunctional Lewis Base Catalyzed Asymmetric N-Allylic Alkylation of 2-Hydroxypyridines DOI

Fei-Ruo Zhang,

Fanshu Cao,

Kui Liu

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(47), P. 8603 - 8608

Published: Nov. 20, 2022

A chiral Lewis base catalyzed enantioselective N-allylic alkylation of 2-hydroxypyridines and MBH carbonates is documented, affording a convenient access to N-alkylated 2-pyridones with up 99% ee yield. Experimental computational studies have revealed that the strong hydrogen bond interaction between catalyst plays crucial role in this reaction for reactivity, chemoselectivity, enantioselectivity.

Language: Английский

Citations

16
Catalytic asymmetric defluorinative allylation of silyl enol ethers DOI Creative Commons
Jordi Duran, Javier Mateos, Albert Moyano

et al.

Chemical Science, Journal Year: 2023, Volume and Issue: 14(26), P. 7147 - 7153

Published: Jan. 1, 2023

The exploitation of an intermolecular Si–F interaction between the substrates, together with chiral Lewis-base catalysis, allows regio-, diastereo- and enantioselective allylation ketone-derived silyl enol ethers allyl fluorides.

Language: Английский

Citations

9