Calix[n]arene-Catalyzed Three-Component Povarov Reaction: Microwave-Assisted Synthesis of Julolidines and Mechanistic Insights.
J Org Chem
; 83(4): 1761-1771, 2018 02 16.
Article
en En
| MEDLINE
| ID: mdl-29337547
ABSTRACT
A new one-pot cascade reaction-based application of Povarov reactions with a p-sulfonic acid calix[4]arene catalyst for the synthesis of a series of 34 julolidine derivatives with substituents at C8 or C9 in good to excellent yields is reported. These microwave-assisted reactions proceeded efficiently, had short reaction times, were metal-free, were low cost, and used an inexpensive, easily available and nontoxic catalyst. These advantages, along with a simple workup procedure, make this protocol a very efficient and green alternative to the traditional methods for constructing these types of N-heterocyclic skeletons. In addition, this protocol allows the formation of julolidine structures, which requires the construction of four new C-C bonds and two C-N bonds. A mechanism for the Povarov reaction involving a stepwise sequence via ionic intermediates was proposed and validated.
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Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
J Org Chem
Año:
2018
Tipo del documento:
Article
País de afiliación:
Brasil