Heterogeneous Synergistic Catalysis for Promoting Aza-Michael–Henry Tandem Reaction for the Synthesis of Chiral 3-Nitro-1,2-Dihydroquinoline

Heterogeneous synergistic catalysis by SBA-15 immobilized chiral amines catalysts has promoted efficient aza-Michael–Henry tandem reaction for the synthesis of chiral 3-Nitro-1,2-Dihydroquinoline. Final products in the asymmetric aza-Michael–Henry cascade reactions between 2-aminobenzaldehyde and β-nitrostyrolene were afforded in a yield of 85% and an enantiomeric excess (ee) value of 98% on (S)-(–)-2-aminomethyl-1-ethylpyrrolidine immobilized SBA-15. SBA-15-AEP catalyst has been also extended to the asymmetric aza-Michael–Henry cascade reaction of substituted R1-2-aminobenzaldehyde and R2-substituted nitroolefin. The heterogeneous synergistic mechanism for both tertiary amine and secondary amine immobilized mesoporous has been proposed in detail including the geometrical constraints in the ee promotion.

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Regio-, Stereo- and Enantioselective α-Addition of Carbonyl Nucleo-philes to Allenamides Catalyzed by a Synergistic Copper/Enamine System

10.26434/chemrxiv.11830935.v1 ◽

2020 ◽

Author(s):

Rémi Blieck ◽

Sebastien Lemouzy ◽

Marc Taillefer ◽

Florian Monnier

Keyword(s):

Catalytic System ◽

Secondary Amine ◽

Primary Amine ◽

Synergistic Catalysis ◽

Enantioselective Addition ◽

Amine Catalysts

A dual copper/enamine catalytic system is found to enable an intermolecular enantioselective α-addition of various carbonyl nucleophiles to allenamides. Secondary amine catalysts allowed the highly enantioselective addition of aldehydes, while using primary amine catalysts led to the enantioselective addition of ketoester nucleophiles. The process was found to be highly regio-, stereo- and enantio-selective and represented the first allene hydrofunctionalization using an synergistic catalysis involving copper

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Synthesis of 1,2,3-Triazole-Fused Indole Derivatives via Copper-Catalyzed Cascade Reaction

Synthesis ◽

10.1055/a-1364-9308 ◽

2021 ◽

Author(s):

Fengtao Zhou ◽

Qiuyu Zhang ◽

Kashif Majeed ◽

Bangjie Liu

Keyword(s):

Quantum Efficiency ◽

Photophysical Properties ◽

Cascade Reaction ◽

Tandem Reaction ◽

Indole Derivatives ◽

Wide Range

AbstractA copper-catalyzed tandem reaction has been developed for the synthesis of 1,2,3-triazole-fused indole derivatives. This protocol allowed us to access a wide range of 1,2,3-triazole-fused indole derivatives in moderate to excellent yields. The 1,2,3-triazole-fused indole derivatives emit blue and greenish light when excited at 365 nm. The products were further explored for their quantum efficiency and photophysical properties.

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Secondary Amine Catalyzed Cascade Reactions

Asymmetric Organocatalysis 2 ◽

10.1055/sos-sd-205-00568 ◽

2012 ◽

pp. 1

Author(s):

Y. -C. Chen ◽

H. -L. Cui

Keyword(s):

Secondary Amine ◽

Cascade Reactions

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Parallel Interconnected Kinetic Asymmetric Transformation (PIKAT) with an Immobilized ω-Transaminase in Neat Organic Solvent

Molecules ◽

10.3390/molecules25092140 ◽

2020 ◽

Vol 25 (9) ◽

pp. 2140 ◽

Cited By ~ 1

Author(s):

Wesley Böhmer ◽

Lucien Koenekoop ◽

Timothée Simon ◽

Francesco G. Mutti

Keyword(s):

Kinetic Resolution ◽

Enantiomeric Excess ◽

Molar Ratio ◽

Chiral Amines ◽

Aqueous Environment ◽

Chiral Amine ◽

Parallel Kinetic Resolution ◽

Pharmaceutical Manufacture ◽

Prochiral Ketones ◽

Asymmetric Transformation

Comprising approximately 40% of the commercially available optically active drugs, α-chiral amines are pivotal for pharmaceutical manufacture. In this context, the enzymatic asymmetric amination of ketones represents a more sustainable alternative than traditional chemical procedures for chiral amine synthesis. Notable advantages are higher atom-economy and selectivity, shorter synthesis routes, milder reaction conditions and the elimination of toxic catalysts. A parallel interconnected kinetic asymmetric transformation (PIKAT) is a cascade in which one or two enzymes use the same cofactor to convert two reagents into more useful products. Herein, we describe a PIKAT catalyzed by an immobilized ω-transaminase (ωTA) in neat toluene, which concurrently combines an asymmetric transamination of a ketone with an anti-parallel kinetic resolution of an amine racemate. The applicability of the PIKAT was tested on a set of prochiral ketones and racemic α-chiral amines in a 1:2 molar ratio, which yielded elevated conversions (up to >99%) and enantiomeric excess (ee, up to >99%) for the desired products. The progress of the conversion and ee was also monitored in a selected case. This is the first report of a PIKAT using an immobilized ωTA in a non-aqueous environment.

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Synthesis of spiro[benzo[4,5]imidazo[2,1-b][1,3]thiazole-2,3-thiolane]s via sulfa-Michael/aldol cascade reactions

Journal of Chemical Research ◽

10.1177/1747519819831898 ◽

2019 ◽

Vol 43 (1-2) ◽

pp. 63-66 ◽

Cited By ~ 1

Author(s):

Jiaying Lei ◽

Xinliang Fu ◽

Yulin Huang ◽

Xiaofang Li

Keyword(s):

Mass Spectrometry ◽

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

High Resolution ◽

High Resolution Mass Spectrometry ◽

Cascade Reactions ◽

Cascade Reaction ◽

Crystallographic Analysis ◽

X Ray ◽

Resolution Mass

The sulfa-Michael/aldol cascade reaction of ( Z)-2-arylmethylidene-benzo[4,5]imidazo[2,1- b]thiazol-3(2H)-ones and 1,4-dithiane-2,5-diol afforded novel 2-aryl-4-hydroxy-spiro[benzo[4,5]imidazo[2,1- b][1,3]thiazole-2,3-thiolan]-3-ones in moderate yields. The structures of all the products were characterized thoroughly by nuclear magnetic resonance, infrared and high-resolution mass spectrometry together with X-ray crystallographic analysis.

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Brushing the surface: cascade reactions between immobilized nanoreactors

Nanoscale ◽

10.1039/c9nr08502e ◽

2020 ◽

Vol 12 (3) ◽

pp. 1551-1562 ◽

Cited By ~ 3

Author(s):

Dalin Wu ◽

Serena Rigo ◽

Stefano Di Leone ◽

Andrea Belluati ◽

Edwin C. Constable ◽

...

Keyword(s):

Polymer Brushes ◽

Cascade Reactions ◽

Cascade Reaction

A tandem cascade reaction between polymer brushes-supported nanoreactors has been demonstrated.

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Synergistic catalysis: enantioselective cyclopropanation of alkylidene benzoxazoles by Pd(ii) and secondary amine catalysis. Scope, limitations and mechanistic insight

Organic Chemistry Frontiers ◽

10.1039/c7qo00858a ◽

2018 ◽

Vol 5 (5) ◽

pp. 806-812 ◽

Cited By ~ 6

Author(s):

Marta Meazza ◽

Victor Polo ◽

Pedro Merino ◽

Ramon Rios

Keyword(s):

Dft Calculations ◽

Secondary Amine ◽

Ring Opening ◽

Synergistic Catalysis ◽

Mechanistic Insight ◽

Amine Catalysis

An enantioselective synergistic cascade cyclopropanation/NHC catalyzed ring opening has been reported. DFT calculations have been performed to confirm the mechanism.

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Diversity-Oriented Synthesis of Natural Products via Gold-Catalyzed Cascade Reactions

Synlett ◽

10.1055/s-0037-1610126 ◽

2018 ◽

Vol 29 (12) ◽

pp. 1552-1571 ◽

Cited By ~ 11

Author(s):

Jianxian Gong ◽

Zhen Yang ◽

Yueqing Gu ◽

Ceheng Tan

Keyword(s):

Natural Products ◽

Total Synthesis ◽

Cascade Reactions ◽

Cascade Reaction ◽

Biologically Active ◽

Synthetic Methods ◽

Left Wing ◽

Asymmetric Total Synthesis ◽

Diversity Oriented Synthesis ◽

Active Natural

This account describes our group’s latest research in the field of diversity-oriented synthesis of natural products via gold-catalyzed cascade reactions. We present two general strategies based on gold-catalyzed cycloisomerization: a gold-catalyzed cascade reaction of 1,7-diynes and a pinacol-terminated gold-catalyzed cascade reaction. We highlight our development of synthetic methods for the construction of biologically active natural products by using these two strategies.1 Introduction2 Gold-Catalyzed Cascade Reactions of 1,7-Diynes2.1 Collective Synthesis of C15 Oxygenated Drimane-Type Sesquiterpenoids2.2 Synthesis of Left-Wing Fragment of Azadirachtin I2.3 Collective Synthesis of Cladiellins3 Pinacol-Terminated Gold-Catalyzed Cascade Reaction3.1 Asymmetric Formal Total Synthesis of (+)-Cortistatins3.2 Total Synthesis of Orientalol F3.3 Asymmetric Total Synthesis of (–)-Farnesiferol C4 Summary and Outlook

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