Intramolecular 1,3-dipolar cycloaddition of stabilized azomethine ylides to unactivated dipolarophiles

1992 ◽  
Vol 57 (26) ◽  
pp. 7056-7066 ◽  
Author(s):  
Brad R. Henke ◽  
Andrew J. Kouklis ◽  
Clayton H. Heathcock
Keyword(s):  
Azomethine Ylides ◽  
Dipolar Cycloaddition ◽  
Stabilized Azomethine Ylides

Regio- and stereoselective 1,3-dipolar cycloaddition reactions between arylideneacetones and stabilized azomethine ylides obtained from ninhydrin and indenoquinoxalinones

2017 ◽  
Vol 53 (12) ◽  
pp. 1315-1323 ◽  
Author(s):  
Alexey Yu. Barkov ◽  
Nikolay S. Zimnitskiy ◽  
Igor B. Kutyashev ◽  
Vladislav Yu. Korotaev ◽  
Vyacheslav Ya. Sosnovskikh
Keyword(s):  
Azomethine Ylides ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
Stabilized Azomethine Ylides

scholarly journals Taniaphos·AgF-catalyzed enantioselective 1,3-dipolar cycloaddition of stabilized azomethine ylides derived from 2,2-dimethoxyacetaldehyde

Tetrahedron ◽  
2016 ◽  
Vol 72 (40) ◽  
pp. 6043-6051 ◽  
Author(s):  
Alberto Cayuelas ◽  
Olatz Larrañaga ◽  
Carmen Nájera ◽  
José M. Sansano ◽  
Abel de Cózar ◽  
...  
Keyword(s):  
Azomethine Ylides ◽  
Dipolar Cycloaddition ◽  
Stabilized Azomethine Ylides

scholarly journals Synthesis of pyrrolizidines and indolizidines by multicomponent 1,3-dipolar cycloaddition of azomethine ylides

2019 ◽  
Vol 91 (4) ◽  
pp. 575-596 ◽  
Author(s):  
Carmen Nájera ◽  
José Miguel Sansano
Keyword(s):  
Amino Acid ◽  
Azomethine Ylides ◽  
Azomethine Ylide ◽  
Dipolar Cycloaddition ◽  
Amino Acid Derivatives ◽  
Reaction Conditions ◽  
Dipolar Cycloadditions ◽  
Spiro Derivatives ◽  
Stabilized Azomethine Ylides

Abstract Different multicomponent 1,3-dipolar cycloadditions (1,3-DC) of cyclic α-amino acid derivatives with aldehydes and dipolarophiles have been described as efficient and simple methodologies for the synthesis of the pyrrolidine unit of pyrrolizidines and indolizidines. When free cyclic α-amino acids are used, a thermal promoted decarboxylative process generates in situ the corresponding non-stabilized azomethine ylides, which afforded the corresponding pyrrolizidines and indolizidines with a hydrogen in the bicyclic units. This methodology has been employed to the synthesis of complex systems including spiro derivatives when ketones are used as carbonyl component. In addition, working with cyclic α-amino acid derived esters, the three-component 1,3-DC takes place under milder reaction conditions giving the corresponding pyrrolizidines and indolizidines with an alkoxycarbonyl group in the bridge adjacent carbon to the nitrogen. This methodology can be carried out by a double consecutive or stepwise 1,3-DC to provide pyrrolizidines via the precursor prolinates. The conformation of the azomethine ylide controls the endo/exo diastereoselectivity of the 1,3-DC.

scholarly journals A General Pyrrolidine Synthesis via Iridium-Catalyzed Reductive Azomethine Ylide Generation from Tertiary Amides & Lactams

2021 ◽  
Author(s):  
Ken Yamazaki ◽  
Pablo Gabriel ◽  
Graziano Di Carmine ◽  
Julia Pedroni ◽  
Mirxan Farizyan ◽  
...  
Keyword(s):  
Density Functional ◽  
Azomethine Ylides ◽  
Azomethine Ylide ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
Reaction Conditions ◽  
Functional Theory ◽  
Efficient Access ◽  
Stabilized Azomethine Ylides ◽  
Tertiary Amides

A new iridium-catalyzed reductive generation of both stabilized and unstabilized azomethine ylides and their application to functionalized pyrrolidine synthesis via [3+2] dipolar cycloaddition reactions is described. Proceeding under mild reaction conditions from both amide and lactam precursors possessing a suitably positioned electron-withdrawing or a trimethylsilyl group, using catalytic Vaska’s complex [IrCl(CO)(PPh3)2] and tetramethyldisiloxane (TMDS) as a terminal reductant, a broad range of (un)stabilized azomethine ylides were accessible. Subsequent, regio- and diastereoselective, inter- and intramolecular, dipolar cycloaddition reactions with variously substituted electron-poor alkenes enabled ready and efficient access to structurally complex pyrrolidine architectures. Density functional theory (DFT) calculations of the dipolar cycloaddition reactions uncovered an intimate balance between asynchronicity and interaction energies of transition structures which ultimately control the unusual selectivities observed in certain cases.

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