The reaction of 2,4-diphenyl-4,5-dihydro-1,3-oxazol-5-one 1 with 4-phenyl-N-tosyl-1-azabuta-1,3-diene 2 has been investigated using different experimental conditions. Whereas at room temperature the kinetically controlled Michael adduct 3 was isolated, at 110°C products 4, 5, 6 and 7 were obtained. Their formation is explained according to 1,3-dipolar cycloaddition and nucleophilic addition, both related to the dual nature of the azlactone 1. The reactivity of azlactone 1 towards imine 2, which is different from that observed with N-alkyl- and N-aryl-1-azabuta-1,3-dienes, is explained on the basis of the electronic effects exerted by the tosyl substituent.
|Titolo:||Reaction of 2,4-diphenyl-4,5-dihydro-1,3-oxazol-5-one with 4-phenyl-N-tosyl-1-azabuta-1,3-diene : C=C versus C=N double bond addition|
DALLA CROCE, PIERO (Primo)
LA ROSA, CONCETTA (Ultimo)
|Settore Scientifico Disciplinare:||Settore CHIM/06 - Chimica Organica|
|Data di pubblicazione:||1994|
|Digital Object Identifier (DOI):||10.1039/P19940002499|
|Appare nelle tipologie:||01 - Articolo su periodico|