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

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.

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

Current Organic Chemistry ◽

10.2174/1385272824999200407093625 ◽

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.

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

Tetrahedron ◽

10.1016/j.tet.2021.132220 ◽

2021 ◽

pp. 132220

Author(s):

Ken-ichi Yamada ◽

Shinichi Fujiwara ◽

Tsubasa Inokuma ◽

Masayuki Sugano ◽

Yousuke Yamaoka ◽

...

Keyword(s):

Conjugate Addition ◽

Chiral Auxiliary

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

Synlett ◽

10.1055/a-1353-7605 ◽

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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Syntheses of Spiro(2-oxopyrrolidinyl)-5,4′-pyrazolones via Organocatalyzed Michael/Ammonolysis Cascade Reaction of 4-Aminopyrazolones and α,β-Unsaturated Acyl Phosphates

Synlett ◽

10.1055/a-1362-0296 ◽

2021 ◽

Author(s):

Lin Chen ◽

You-Fen Li ◽

Zheng-Jun Chen ◽

Wen-Ya Jiao ◽

Zhi-Jiao Chen

Keyword(s):

Drug Discovery ◽

Chemical Biology ◽

Cascade Reaction ◽

Unsaturated Acyl

AbstractThe efficient organocatalyzed Michael/ammonolysis cascade reaction of N-protected 4-aminopyrazolones and α,β-unsaturated acyl phosphates has been developed. This tactic gives rise to architecturally multifarious spiro(2-oxopyrrolidinyl)-5,4′-pyrazolones in good productiveness (up to 88% yield) and with moderate to good diastereoselectivities (up to 20:1 dr). These novel hybrid heterocycles would be promising candidates for drug-discovery programs and chemical biology.

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α,β-Unsaturated acyl ammonium species as reactive intermediates in organocatalysis: an update

Organic & Biomolecular Chemistry ◽

10.1039/d0ob02208j ◽

2020 ◽

Author(s):

Jacqueline Bitai ◽

Matthew Westwood ◽

Andrew D Smith

Keyword(s):

Reactive Intermediates ◽

Domino Reactions ◽

Michael Additions ◽

Unsaturated Acyl

α,β-Unsaturated acyl ammonium species are versatile intermediates that have been applied in a variety of transformation including Michael additions, domino reactions and cycloadditions. Many of these transformations are promoted by...

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Enantiopure Derivatives of Aza-Baylis-Hillman Adducts by Subsequent SN′-SN′ Reactions of Acylcarbamates Bearing a Chiral Auxiliary

Molecules ◽

10.3390/molecules14082824 ◽

2009 ◽

Vol 14 (8) ◽

pp. 2824-2835 ◽

Cited By ~ 2

Author(s):

Gianluca Martelli ◽

Eleonora Marcucci ◽

Mario Orena ◽

Samuele Rinaldi

Keyword(s):

Chiral Auxiliary ◽

Derivatives Of

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