Solvent-controlled diastereoselectivity in tryptophan-catalyzed Mannich reactions

Abstract Solvent effects in the L-tryptophan-catalyzed Mannich reaction between hydroxyacetone and glyoxylate imines have been examined. The use of a DMSO/1-butanol (4:1 v/v) mixture as solvent at rt provided the expected Mannich adducts in good yields, high anti-diastereoselectivity (up to 10.3:1 anti/syn ratio) and excellent enantioselectivities (up to >99.9% ee for the anti isomer).

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Recent advances and prospects in the Zn-catalysed Mannich reaction

RSC Advances ◽

10.1039/d0ra10772g ◽

2021 ◽

Vol 11 (16) ◽

pp. 9098-9111

Author(s):

Salahudeen Shamna ◽

C. M. A. Afsina ◽

Rose Mary Philip ◽

Gopinathan Anilkumar

Keyword(s):

Carbonyl Compound ◽

Secondary Amine ◽

Mannich Reaction ◽

Mannich Base ◽

Mannich Reactions ◽

Recent Advances ◽

Primary Secondary Amine

Amino alkylation of an acidic α-proton of a carbonyl by formaldehyde and a primary/secondary amine or ammonia, affording a β-amino-carbonyl compound also known as a Mannich base is a valuable reaction. We focus on recent advances in Zn catalysed Mannich reactions.

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Squaramide-catalyzed asymmetric Mannich reactions between 3-fluorooxindoles and pyrazolinone ketimines

Organic & Biomolecular Chemistry ◽

10.1039/c9ob01350d ◽

2019 ◽

Vol 17 (30) ◽

pp. 7182-7191 ◽

Cited By ~ 4

Author(s):

Qing-Da Zhang ◽

Bo-Liang Zhao ◽

Bing-Yu Li ◽

Da-Ming Du

Keyword(s):

Mannich Reaction ◽

Mannich Reactions ◽

Quaternary Stereocenters

Squaramide-catalyzed asymmetric Mannich reaction between 3-fluorooxindoles and pyrazolinone ketimines afforded fluorinated amino-pyrazolone-oxindoles with two quaternary stereocenters in good to excellent yields with excellent stereoselectivities.

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Polyelectrolyte Brønsted acid catalyzed three-component Mannich reactions accelerated by emulsion

RSC Advances ◽

10.1039/c6ra04180a ◽

2016 ◽

Vol 6 (45) ◽

pp. 39343-39347 ◽

Cited By ~ 6

Author(s):

Xi Chen ◽

Huaming Sun ◽

Yanlong Luo ◽

Yajun Jian ◽

Ya Wu ◽

...

Keyword(s):

Polyacrylic Acid ◽

Mannich Reaction ◽

Bronsted Acid ◽

Brønsted Acid ◽

Mannich Reactions ◽

Brönsted Acid ◽

Acid Catalyzed

An effective polyelectrolyte Brønsted acid (polyacrylic acid) catalyzed three-component Mannich reaction accelerated by emulsion has been developed.

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A versatile access to vicinal diamine motifs by highly anti-selective asymmetric vinylogous Mannich reactions: an efficient total synthesis of (+)-absouline

Organic Chemistry Frontiers ◽

10.1039/c6qo00022c ◽

2016 ◽

Vol 3 (6) ◽

pp. 683-692 ◽

Cited By ~ 10

Author(s):

Jian-Liang Ye ◽

Hang Chen ◽

Yu-Feng Zhang ◽

Pei-Qiang Huang

Keyword(s):

Total Synthesis ◽

Mannich Reaction ◽

Efficient Synthesis ◽

Mannich Reactions

An anti-stereoselective vinylogous Mannich reaction between 2-TBSO-pyrrole and N-tert-butanesulfinyl imines and its application to the efficient synthesis of (+)-absouline were reported.

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Diaryliodonium salts as efficient Lewis acid catalysts for direct three component Mannich reactions

RSC Advances ◽

10.1039/c5ra00209e ◽

2015 ◽

Vol 5 (32) ◽

pp. 25485-25488 ◽

Cited By ~ 31

Author(s):

Yanxia Zhang ◽

Jianwei Han ◽

Zhen-Jiang Liu

Keyword(s):

Lewis Acid ◽

Mannich Reaction ◽

Solvent Free ◽

Acid Catalysts ◽

Lewis Acid Catalysts ◽

Mannich Reactions ◽

Highly Active ◽

Diaryliodonium Salts ◽

Solvent Free Conditions

Diaryliodonium(iii) salts, as highly active and versatile Lewis acid catalysts for the direct three component Mannich reaction under solvent free conditions, have been investigated.

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New tartrate based cyclic phosphoric acids as organocatalysts in Mannich reactions

Asymmetric Catalysis ◽

10.1515/asorg-2016-0001 ◽

2016 ◽

Vol 3 (1) ◽

Author(s):

Tuvshinjargal Budragchaa ◽

Michael Abraham ◽

Wolfgang Schöfberger ◽

Alexander Roller ◽

Michael Widhalm

Keyword(s):

Crystal Structure ◽

Dft Calculations ◽

Structure Analysis ◽

Mannich Reaction ◽

Structural Variation ◽

Crystal Structure Analysis ◽

Mannich Reactions ◽

Optimization Study ◽

The Mannich Reaction ◽

Phosphoric Acids

Abstract Cyclic phosphoric acids have attracted much attention as chiral organocatalysts. While binaphthol based ligands have been extensively used in various transformations, the analogous TADDOL-type ligands are less explored. A library of seventeen cyclic phosphoric acids with structural variation of the TADDOL backbone were synthesized and an optimization study of the Mannich reaction of aromatic N-(2-hydroxyphenyl)imines with 2,2-dimethyl-1-methoxy-silylenolate was performed. Enantioselectivities between 96% (S) and 70% (R) were observed and a rationalisation, based on crystal structure analysis and DFT calculations, is provided.

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