Enantioselective (3+2)-Annulation of β-Keto Esters with Azoalkenes towards Bicyclic Dihydropyrroles via Cooperative Palladium and Brønsted Acid Catalysis DOI
Christoph Schneider,

Till Friedmann,

Daniel A. Mireles-Chávez

et al.

Synlett, Journal Year: 2023, Volume and Issue: 35(09), P. 997 - 1000

Published: Nov. 13, 2023

Abstract A cooperative catalytic process through palladium and Brønsted acid activation is developed for the conjugate addition of cyclic β-keto esters to azoalkenes directly followed by hemiaminal formation upon cyclization. This transformation enabled utilizing chiral Pd-aqua complexes as combined acid–base catalysts. Thus, bicyclic highly functionalized dihydropyrroles with two contiguous quaternary stereogenic centers are formed in excellent yields single diastereomers exceptional enantioselectivity.

Language: Английский

Alkylation of Phenols with 4,6-Di-tert-butyl-3-methoxymethylcatechol. Antiradical Activity of Sterically Hindered Catecholphenols DOI
Anastasiya E. Tarakanova,

Н. Д. Анисимова,

D. A. Martynova

et al.

Russian Journal of General Chemistry, Journal Year: 2023, Volume and Issue: 93(S3), P. S629 - S638

Published: Dec. 1, 2023

Language: Английский

Citations

2
New Developments of Chiral Palladium‐Aqua Complexes as Cooperative Brønsted Acid‐Base Catalysts in Organic Synthesis DOI Creative Commons

Cornelius V. Gärtner,

Christoph Schneider

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(10)

Published: April 12, 2023

Abstract Based upon their exceptional reactivity as cooperative Brønsted acid‐base catalysts chiral diphosphane Pd‐aqua complexes have successfully been utilized in a broad range of asymmetric transformations. Originally discovered by Sodeoka 25 years ago, they readily form reactive Pd enolates deprotonation β‐dicarbonyl compounds and simultaneously, acid liberated from the catalyst activates electrophile. After initial report some ensuing papers had published early 2000s, field lay dormant for more than decade. In recent years, however, new developments towards enantioselective synthesis various heterocycles other useful evolved which take advantage unique properties complexes.

Language: Английский

Citations

1
Stereoselective Construction of Vicinal Quaternary Stereocenters via the 1,6-Conjugate Addition of β,β-Disubstituted N-Sulfinyl Metalloenamines to Isatin-Derived para-Quinone Methides DOI
Chong‐Dao Lu,

Zheng-Fei Li

Synthesis, Journal Year: 2023, Volume and Issue: 56(05), P. 828 - 850

Published: Dec. 6, 2023

Abstract A 1,6-conjugate addition reaction of β,β-disubstituted N-tert-butanesulfinyl metalloenamines, generated via stereospecific α-deprotonation enantioenriched α,α-disubstituted ketimines or deprotonation the NH in geometry-defined enesulfinamides, with isatin-derived para-quinone methides is developed to build vicinal quaternary stereocenters high stereocontrol. The resulting 3,3-disubstituted oxindoles contain a less-accessible acyclic stereogenic carbon substituted two sterically and electronically similar groups at α-position imino group. This protocol constitutes rare example stereoselective construction conjugate enolates/aza-enolates bearing β-substituents.

Language: Английский

Citations

1
Recent Progress on NHC‐Catalyzed 1,6‐Conjugate Addition Reactions DOI
Jun Sun, Shichun Jiang,

Yonggui Liu

et al.

The Chemical Record, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 17, 2024

Abstract As a significant variant of the Michael reaction, 1,6‐addition reaction has undergone considerable development over past decade. This effective strategy enables synthesis variety novel and potentially bioactive functional molecules. In this review, we summarize recent progress in NHC‐catalyzed reactions, highlighting their efficiency rapid complex We also provide our perspectives on future dynamic highly active research area.

Language: Английский

Citations

0
Enantioselective (3+2)-Annulation of β-Keto Esters with Azoalkenes towards Bicyclic Dihydropyrroles via Cooperative Palladium and Brønsted Acid Catalysis DOI
Christoph Schneider,

Till Friedmann,

Daniel A. Mireles-Chávez

et al.

Synlett, Journal Year: 2023, Volume and Issue: 35(09), P. 997 - 1000

Published: Nov. 13, 2023

Abstract A cooperative catalytic process through palladium and Brønsted acid activation is developed for the conjugate addition of cyclic β-keto esters to azoalkenes directly followed by hemiaminal formation upon cyclization. This transformation enabled utilizing chiral Pd-aqua complexes as combined acid–base catalysts. Thus, bicyclic highly functionalized dihydropyrroles with two contiguous quaternary stereogenic centers are formed in excellent yields single diastereomers exceptional enantioselectivity.

Language: Английский

Citations

0