(S,S)-(+)-Pseudoephedrine as Chiral Auxiliary in Asymmetric Aza-Michael Reactions. Unexpected Selectivity Change when Manipulating the Structure of the Auxiliary

2005 ◽  
Vol 70 (22) ◽  
pp. 8790-8800 ◽  
Author(s):  
Juan Etxebarria ◽  
Jose L. Vicario ◽  
Dolores Badia ◽  
Luisa Carrillo ◽  
Nerea Ruiz
Keyword(s):  
Chiral Auxiliary ◽  
Michael Reactions ◽  
Selectivity Change

scholarly journals (S,S)-(+)-Pseudoephedrine as Chiral Auxiliary in Asymmetric Aza-Michael Reactions. Unexpected Selectivity Change when Manipulating the Structure of the Auxiliary.

ChemInform ◽  
2006 ◽  
Vol 37 (11) ◽  
Author(s):  
Juan Etxebarria ◽  
Jose L. Vicario ◽  
Dolores Badia ◽  
Luisa Carrillo ◽  
Nerea Ruiz
Keyword(s):  
Chiral Auxiliary ◽  
Michael Reactions ◽  
Selectivity Change

Pseudoephedrine as a Chiral Auxiliary for Asymmetric Michael Reactions:  Synthesis of 3-Aryl-δ-lactones

2002 ◽  
Vol 4 (11) ◽  
pp. 1963-1966 ◽  
Author(s):  
Jacqueline H. Smitrovich ◽  
Geneviève N. Boice ◽  
Chuanxing Qu ◽  
Lisa DiMichele ◽  
Todd D. Nelson ◽  
...  
Keyword(s):  
Chiral Auxiliary ◽  
Michael Reactions

Diastereoselective sulfa-Michael reactions controlled by a biomass-derived chiral auxiliary

Tetrahedron ◽  
2019 ◽  
Vol 75 (29) ◽  
pp. 3894-3903 ◽  
Author(s):  
Julian Klepp ◽  
Harald Podversnik ◽  
Johannes Puschnig ◽  
Andrew Wallace ◽  
Ben W. Greatrex
Keyword(s):  
Chiral Auxiliary ◽  
Michael Reactions

ChemInform Abstract: Pseudoephedrine as a Chiral Auxiliary for Asymmetric Michael Reactions: Synthesis of 3-Aryl-δ-lactones.

ChemInform ◽  
2010 ◽  
Vol 33 (42) ◽  
pp. no-no
Author(s):  
Jacqueline H. Smitrovich ◽  
Genevieve N. Boice ◽  
Chuanxing Qu ◽  
Lisa DiMichele ◽  
Todd D. Nelson ◽  
...  
Keyword(s):  
Chiral Auxiliary ◽  
Michael Reactions

A Poly(ethylene glycol) Supported Chiral Auxiliary for Asymmetric Michael Reactions

Synlett ◽  
2005 ◽  
pp. 465-468 ◽  
Author(s):  
Jens Christoffers ◽  
Burkard Kreidler ◽  
Angelika Baro
Keyword(s):  
Ethylene Glycol ◽  
Chiral Auxiliary ◽  
Poly Ethylene Glycol ◽  
Michael Reactions ◽  
Poly Ethylene

Enantioselective Michael Addition of Malonates to Enones

2020 ◽  
Vol 24 (7) ◽  
pp. 746-773
Author(s):  
Péter Bakó ◽  
Tamás Nemcsok ◽  
Zsolt Rapi ◽  
György Keglevich
Keyword(s):  
Michael Addition ◽  
Activity Relationship ◽  
Chalcone Derivatives ◽  
Michael Additions ◽  
Michael Reactions ◽  
Structure Activity ◽  
Cyclic Enones ◽  
Michael Acceptors ◽  
Relationship Of ◽  
Enantioselective Catalysts

: Many catalysts were tested in asymmetric Michael additions in order to synthesize enantioenriched products. One of the most common reaction types among the Michael reactions is the conjugated addition of malonates to enones making it possible to investigate the structure–activity relationship of the catalysts. The most commonly used Michael acceptors are chalcone, substituted chalcones, chalcone derivatives, cyclic enones, while typical donors may be dimethyl, diethyl, dipropyl, diisopropyl, dibutyl, di-tert-butyl and dibenzyl malonates. This review summarizes the most important enantioselective catalysts applied in these types of reactions.

An Overview of the One-pot Synthesis of Imidazolines

2020 ◽  
Vol 24 (20) ◽  
pp. 2341-2355
Author(s):  
Thaipparambil Aneeja ◽  
Sankaran Radhika ◽  
Mohan Neetha ◽  
Gopinathan Anilkumar
Keyword(s):  
Asymmetric Catalysis ◽  
Organic Compounds ◽  
Ring Opening ◽  
Ecological Impact ◽  
Chiral Auxiliary ◽  
One Pot ◽  
One Pot Synthesis ◽  
The One ◽  
Synthetic Intermediate ◽  
Heterocyclic Moiety

One-pot syntheses are a simple, efficient and easy methodology, which are widely used for the synthesis of organic compounds. Imidazoline is a valuable heterocyclic moiety used as a synthetic intermediate, chiral auxiliary, chiral catalyst and a ligand for asymmetric catalysis. Imidazole is a fundamental unit of biomolecules that can be easily prepared from imidazolines. The one-pot method is an impressive approach to synthesize organic compounds as it minimizes the reaction time, separation procedures, and ecological impact. Many significant one-pot methods such as N-bromosuccinimide mediated reaction, ring-opening of tetrahydrofuran, triflic anhydrate mediated reaction, etc. were reported for imidazoline synthesis. This review describes an overview of the one-pot synthesis of imidazolines and covers literature up to 2020.

Indium Bromide-catalyzed Unprecedented Hydrogenolysis: A Novel One-Pot Synthesis of Per-O-Acetylated β-carboxymethyl O and S-glycosides

2020 ◽  
Vol 24 (8) ◽  
pp. 900-908
Author(s):  
Ram Naresh Yadav ◽  
Amrendra K Singh ◽  
Bimal Banik
Keyword(s):  
Asymmetric Synthesis ◽  
Chiral Auxiliary ◽  
Bioactive Molecules ◽  
One Pot ◽  
Enantiomerically Pure ◽  
Stereoselective Glycosylation ◽  
One Pot Synthesis ◽  
Wide Range

Numerous O (oxa)- and S (thia)-glycosyl esters and their analogous glycosyl acids have been accomplished through stereoselective glycosylation of various peracetylated bromo sugar with benzyl glycolate using InBr3 as a glycosyl promotor followed by in situ hydrogenolysis of resulting glycosyl ester. A tandem glycosylating and hydrogenolytic activity of InBr3 has been successfully investigated in a one-pot procedure. The resulting synthetically valuable and virtually unexplored class of β-CMGL (glycosyl acids) could serve as an excellent potential chiral auxiliary in the asymmetric synthesis of a wide range of enantiomerically pure medicinally prevalent β-lactams and other bioactive molecules of diverse medicinal interest.

The Rationale for Stereoinduction in Conjugate Addition to Alkylidenemalonates Bearing a Menthol-derived Chiral Auxiliary

Tetrahedron ◽  
2021 ◽  
pp. 132220
Author(s):  
Ken-ichi Yamada ◽  
Shinichi Fujiwara ◽  
Tsubasa Inokuma ◽  
Masayuki Sugano ◽  
Yousuke Yamaoka ◽  
...  
Keyword(s):  
Conjugate Addition ◽  
Chiral Auxiliary

Asymmetric Synthesis of α-Alkylated γ-Lactam via Nickel/8-Quinim-Catalyzed Reductive Alkyl-Carbamoylation of Unactivated Alkene

Synlett ◽  
2021 ◽  
Author(s):  
Xianqing Wu ◽  
Mohini Shrestha ◽  
Yifeng Chen
Keyword(s):  
Functional Group ◽  
Enantioselective Synthesis ◽  
Chiral Auxiliary ◽  
Alkyl Iodide ◽  
General Strategy ◽  
Chemical Bonds ◽  
Mild Conditions ◽  
Chiral Carbon ◽  
Enantioselective Reaction ◽  
Metal Catalyzed

AbstractChiral-auxiliary-mediated synthesis represents the most frequently used synthetic tool for the induction of chirality on α-position of γ-lactams in organic synthesis. However, the general strategy requires the stoichiometric use of chiral reagents with multiple manipulation steps. Transition-metal-catalyzed asymmetric alkene dicarbofunctionalization using readily available substrates under mild conditions allows the simultaneous construction of two vicinal chemical bonds and a chiral carbon center, hence, gain expedient access to chiral heterocycles. Herein, we disclose a Ni-catalyzed enantioselective reaction of 3-butenyl carbamoyl chloride and primary alkyl iodide enabled by a newly designed chiral 8-quinoline imidazoline ligand (8-Quinim). This protocol features broad functional group tolerance and high enantioselectivities, achieving unprecedented synthesis of chiral nonaromatic heterocycles via catalytic reductive protocol.1 Introduction2 Development of 8-Quinim Ligand3 Nickel/8-Quinim-Catalyzed Enantioselective Synthesis of Chiral α-Alkylated γ-Lactam4 Conclusion and Outlook

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