ChemInform Abstract: Synthesis and Stereoselective Reactions of α,β-Unsaturated Acyl Ligands Bound to the Chiral Auxiliary ((η5-C5H5)Fe(CO)(PPh3)): A Review

ChemInform ◽  
1988 ◽  
Vol 19 (1) ◽  
Author(s):  
S. G. DAVIES ◽  
I. M. DORDOR-HEDGECOCK ◽  
R. J. C. EASTON ◽  
S. C. PRESTON ◽  
K. H. SUTTON ◽  
...  
Keyword(s):  
Chiral Auxiliary ◽  
Unsaturated Acyl ◽  
Stereoselective Reactions

scholarly journals DFT Study of Stereoselective Ketene-imine Cycloadditions, Evaluation of Possible Solvent Effects with IEF-PCM

2018 ◽  
Vol 62 (4) ◽  
Author(s):  
Balázs Komjáti ◽  
Bianka Szokol ◽  
Benjámin Kováts ◽  
Péter Kegye ◽  
József Nagy
Keyword(s):  
Experimental Data ◽  
Solvent Effects ◽  
Substituent Effects ◽  
Chiral Auxiliary ◽  
Electrostatic Repulsion ◽  
Chiral Auxiliaries ◽  
Reaction Parameters ◽  
Reaction Proceeds ◽  
Stereoselective Reactions ◽  
Main Factor

The formal [2+2] cycloaddition of ketenes and imines, also known as Staudinger synthesis, is a facile method for the synthesis of biologically important β-lactam derivatives. In this paper two previously reported stereoselective reactions were investigated with computational methods. Our computations support experimental data that a chiral imine, derived from d-glyceraldehyde reacting with ketenes, yields almost exclusively one out of the possible four diastereomers. The reaction proceeds stepwise, first addition of the imine to the ketene yields an intermediate, then the product is formed in a conrotatory electrocyclization. Results indicate that the electrostatic repulsion of the chiral auxiliary group is the main factor of the stereoselectivity, but solvent and substituent effects are not negligible. Calculations were performed at M06-2X/6-31+G** level of theory combined with IEF-PCM solvation, in common solvents such as toluene, THF, dichloromethane, acetonitrile and water. These results provide useful insight for the development of new chiral auxiliaries and optimizing reaction parameters.

Synthesis of α,β-unsaturated acyl ligands bound to the chiral auxiliary [(η5 -C5H5)Fe(CO)(PPh3)]

1985 ◽  
Vol 296 (3) ◽  
pp. c40-c42 ◽  
Author(s):  
Stephen G. Davies ◽  
Robert J.C. Easton ◽  
Jonathan C. Walker ◽  
Peter Warner
Keyword(s):  
Chiral Auxiliary ◽  
Unsaturated Acyl

Face-selective adsorption of a prochiral compound on the chiral pore-surface of a metal–macrocycle framework (MMF) directed towards stereoselective reactions

2021 ◽  
Author(s):  
Shohei Tashiro ◽  
Tsutomu Umeki ◽  
Ryou Kubota ◽  
Mitsuhiko Shionoya
Keyword(s):  
Selective Adsorption ◽  
Porous Metal ◽  
Chiral Auxiliary ◽  
Pore Surface ◽  
Stereoselective Reactions

The chiral pore-surface of a porous metal–macrocycle framework face-selectively adsorbs a prochiral molecule with the aid of a supramolecular chiral auxiliary.

Stereoselective Synthesis 1 Stereoselective Reactions of Carbon—Carbon Double Bonds

2011 ◽  
Author(s):  
J. G. de Vries ◽  
K. Muñiz ◽  
G. Franciò ◽  
W. Leitner ◽  
P. L. Alsters ◽  
...  
Keyword(s):  
Stereoselective Synthesis ◽  
Double Bonds ◽  
Stereoselective 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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