One-Step Synthesis of 1,3,4-Oxadiazines, 4,5,6,7-Tetrahydro-1h-Indoles, and Functionalized Benzo[B]Carbazoles Catalyzed by Rare Earth Metal Triflates and Cooperative Enamine-Bronsted Acid DOI Open Access

Jose Cortes Vazquez

Published: May 1, 2023

Design and development of novel one-step reactions that produce nitrogen-containing scaffolds is an invaluable area chemistry due to the abundance these moieties in natural products biologically active molecules. Discovering methods using uncommon substrates rare earth metals access significant present a challenge. Over course my doctoral studies, I have designed, developed optimized by rarely known afforded important scaffolds. The obtained allow otherwise long-to-synthesize molecules expeditious construction

Language: Английский

Asymmetric aza‐Friedel–Crafts Reaction of Cyclic Ketimines with 5‐Aminopyrazole Derivatives: Expedient Access to Pyrazole‐Based C2‐quaternary Indolin‐3‐Ones DOI

Xiu‐Xiu Qiao,

Yonghui He,

Tao Ma

et al.

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(20)

Published: Jan. 5, 2023

A chiral phosphoric acid-catalyzed enantioselective aza-Friedel-Crafts reaction of 5-aminopyrazole derivatives with cyclic ketimines attached to a neutral functional group is reported. This protocol allows the formation pyrazole-based C2-quaternary indolin-3-ones high enantioselectivities and regioselectivities. Moreover, gram-scale synthesis 5-aminopyrazole-based was performed, no decrease in yield enantioselectivity.

Language: Английский

Citations

20

Asymmetric Synthesis of Triphenylmethanes via Organocatalytic Regio- and Enantioselective Friedel–Crafts Alkylation of Aniline Derivatives DOI
Ruilin Zhang, Bo Liu,

Kaixiong Qiu

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(10), P. 1711 - 1716

Published: March 9, 2023

Herein, we described a highly regio- and enantioselective Friedel–Crafts alkylation of aniline derivatives with in situ generated ortho-quinone methides enabled by chiral phosphoric acid, furnishing wide range enantioenriched triarylmethanes bearing three similar benzene rings high yields (up to 98%) excellent stereoselectivities 98% ee). Furthermore, the large-scale reactions diversified transformations product demonstrate practicality protocol. Density functional theory calculations elucidate origin enantioselectivity.

Language: Английский

Citations

13

Enantioselective construction of chiral gem-difluorinated C2-quaternary indoline via dual MgSO4–CPA-catalyzed asymmetric Mannich reactions DOI

Xinchun Wang,

Xing‐Pin Wei,

Chang-Peng Zou

et al.

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(5), P. 1430 - 1436

Published: Jan. 1, 2024

Herein, the synthesis of 2-(3,3-difluoro-2-phenylindolin-2-yl)-1-phenylethan-1-one scaffolds through asymmetric Mannich reactions between 3,3-difluoro cyclic ketimines and simple ketones is described.

Language: Английский

Citations

4

Catalytic Asymmetric Cyclizative Rearrangement of Anilines and Vicinal Diketones to Access 2,2‐Disubstituted Indolin‐3‐ones DOI Creative Commons

Rui Quan,

Xing‐Zi Li,

Zi‐Qi Wang

et al.

Advanced Science, Journal Year: 2024, Volume and Issue: 11(25)

Published: April 24, 2024

Abstract The efficient synthesis of chiral 2,2‐disubstituted indolin‐3‐ones is great importance due to its significant synthetic and biological applications. However, catalytic enantioselective methods for de novo such heterocycles remain scarce. Herein, a novel cyclizative rearrangement readily available anilines vicinal diketones the one‐step construction enantioenriched presented. reaction proceeds through self‐sorted [3+2] heteroannulation/regioselective dehydration/1,2‐ester shift process. Only phosphoric acid employed promote entire sequence simplify manipulation this protocol. Various common aniline derivatives are successfully applied asymmetric as 1,3‐binuclephiles first time. Remarkably, observed stereoselectivity proposed originate from an amine‐directed regio‐ ortho ‐Csp 2 ‐H addition ketones. A range transformations resulting products demonstrated well.

Language: Английский

Citations

4

α‐Halocarbonyls as a Valuable Functionalized Tertiary Alkyl Source DOI Creative Commons
Takashi Nishikata

ChemistryOpen, Journal Year: 2024, Volume and Issue: unknown

Published: July 11, 2024

Abstract This review introduces the synthetic organic chemical value of α‐bromocarbonyl compounds with tertiary carbons. compound a carbon has been used primarily only as radical initiator in atom transfer polymerization (ATRP) reactions. However, recent development photo‐radical reactions (around 2010), research on use alkyl precursors became popular 2012). As more examples were reported, studied not radicals but also for their applications organometallic and ionic That is, act nucleophiles well electrophiles. The carbonyl group is attractive because it allows skeleton to be converted after reaction, being applied total synthesis. In our survey until 2022, can perform full range necessary synthesis, including multi‐component reactions, cross‐coupling, substitution, cyclization, rearrangement, stereospecific asymmetric α‐Bromocarbonyl have created new trend alkylation, which then had limited reaction patterns focuses how chemistry.

Language: Английский

Citations

4

Silyl Cation-Initiated, Brønsted Acid-Catalyzed Strategy toward Unsymmetrical 3,3-Disubstituted 2-Oxindoles and Azonazine Cores DOI

Jabir Khan,

Naveen Yadav,

Aparna Tyagi

et al.

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(16), P. 11097 - 11111

Published: Aug. 5, 2022

Herein, a mild, metal-free, robust approach for synthesizing valuable and sterically demanding unsymmetrical 3,3-disubstituted 2-oxindoles via reductive cyclization of α-ketoamides is reported. This operationally simple protocol initiated by silyl cation further catalyzed Brønsted acid. We have utilized wide range arenes, amines, thiols as coupling partners with various α-ketoamides. The products were afforded in excellent regioselectivity good functional group tolerance. procedure provides easy access to the scaffolds azonazine its derivatives an syn-diastereoselectivity bearing all-carbon quaternary stereocenters.

Language: Английский

Citations

16

Asymmetric catalytic Friedel–Crafts alkylation with arenes and heteroarenes: construction of 3,3-disubstituted oxindoles DOI

Tinghui Zhang,

Ziwei Zhong,

Zi Zeng

et al.

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(20), P. 5274 - 5283

Published: Jan. 1, 2023

The asymmetric Friedel–Crafts alkylation of 3-bromo-3-substituted oxindoles with arenes and heteroarenes was achieved to synthesize enantioenriched C3-arylated oxindoles.

Language: Английский

Citations

9

HFIP-promoted para-selective alkylation of anilines and phenols with tertiary alkyl bromides DOI

Pengcheng Huang,

Xipeng Jiang,

Du Gao

et al.

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(10), P. 2476 - 2481

Published: Jan. 1, 2023

We have herein reported a hexafluoroisopropanol-promoted para -selective Friedel–Crafts alkylation of arenes. Preliminary mechanistic studies revealed that the intramolecular hydrogen bond network HFIP was key factor in realizing site-selectivity.

Language: Английский

Citations

7

Catalytic Asymmetric Synthesis of Vicinal Quaternary Stereocenters Enabled by Alkylation of α,α-Disubstituted Aldehydes with 3-Bromooxindoles DOI
Longjun Dong, Qi Wang, Jingfeng Zhang

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(15), P. 3086 - 3090

Published: April 9, 2024

An organocatalytic enantioselective alkylation of α,α-disubstituted aldehydes with 3-bromooxindoles is reported. Enantioenriched oxindoles vicinal quaternary stereocenters are accessed by an asymmetric conjugate addition process branched o-azaxylylene intermediates (indol-2-ones). Key to the success highly diastereo- and transformations combined use a triphenylsilyl-protected β-amino alcohol catalyst derived from spiropyrrolidine scaffold 3,5-dinitrobenzoic acid. This study also presents rare example aldehyde formation consecutive stereocenters.

Language: Английский

Citations

2

B(C6F5)3/CPA‐Catalyzed Aza‐Diels–Alder Reaction of 3,3‐Difluoro‐2‐Aryl‐3H‐indoles and Unactivated Dienes DOI

Xing‐Pin Wei,

Xinchun Wang,

Tao Ma

et al.

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(34)

Published: April 16, 2024

Abstract Here we report B(C 6 F 5 ) 3/ CPA‐catalyzed enantioselective aza‐Diels–Alder reaction of 3,3‐difluoro‐2‐Aryl‐3 H ‐indoles with unactivated dienes to access chiral 10,10‐difluoro‐tetrahydropyrido[1,2‐ a ]indoles. This protocol allows the formation pyrazole‐based C2‐quaternary indolin‐3‐ones high enantioselectivities and regioselectivities. Moreover, gram‐scale synthesis ]indole skeleton was successfully achieved without any reduction in both yield enantioselectivity.

Language: Английский

Citations

2