Allylic Acetals as Acrolein Oxonium Precursors in Tandem C−H Allylation and [3+2] Dipolar Cycloaddition

The ruthenium(II)‐catalyzed C−H functionalization of (hetero)aryl azomethine imines with allylic acetals is described. The initial formation of allylidene(methyl)oxoniums from allylic acetals could trigger C(sp2)−H allylation, and subsequent endo‐type [3+2] dipolar cycloaddition of polar azomethine...

Full description

Saved in:
Bibliographic Details
Published in:Angewandte Chemie 2019-07, Vol.131 (28), p.9570-9574
Main Authors: Lee, Heeyoung, Kang, Dahye, Han, Sang Hoon, Chun, Rina, Pandey, Ashok Kumar, Mishra, Neeraj Kumar, Hong, Sungwoo, Kim, In Su
Format: Article
Language:English
Subjects:
Acetals
Acrolein
Allyl compounds
Allylacetale
Aromatic compounds
C-H-Funktionalisierung
Cascade chemical reactions
Celecoxib
Chemical reactions
Chemistry
Computer applications
Cycloaddition
Dipolare Cycloadditionen
Estrone
Imines
Indenopyrazolopyrazolon
Ruthenium
Ruthenium compounds
Tandemreaktionen
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The ruthenium(II)‐catalyzed C−H functionalization of (hetero)aryl azomethine imines with allylic acetals is described. The initial formation of allylidene(methyl)oxoniums from allylic acetals could trigger C(sp2)−H allylation, and subsequent endo‐type [3+2] dipolar cycloaddition of polar azomethine fragments to deliver valuable indenopyrazolopyrazolones. The utility of this method is showcased by the late‐stage functionalization of bioactive molecules such as estrone and celecoxib. Combined experimental and computational investigations elucidate a plausible mechanism of this new tandem reaction. Notably, the reductive transformation of synthesized compounds into biologically relevant diazocine frameworks highlights the importance of the developed methodology. Effizienter Gerüstbau: Eine RuII‐katalysierte C‐H‐Allylierung von (Hetero)arylazomethiniminen mit Allylacetalen, gefolgt von einer intramolekularen endo‐artigen dipolaren [3+2]‐Cycloaddition, ermöglicht den direkten, effizienten Aufbau hoch substituierter Indenopyrazolopyrazolon‐Gerüste in guten bis hohen Ausbeuten.
ISSN:0044-8249
1521-3757
DOI:10.1002/ange.201903983