Lewis acid-promoted hetero Diels-Alder cycloaddition of alpha-acetoxynitroso dienophiles.
[reaction: see text] alpha-Acetoxynitroso compound 3 has been prepared as a new stable, isolable, and reactive dienophile in nitroso Diels-Alder reactions. The yield of the [4 + 2] cycloaddition of alpha-acetoxynitroso dienophile with 1,3-dienes could be enhanced in the presence of 20 mol % Lewis acid. An unexpected retro hetero-Michael reaction from 26 was observed, leading to the cleavage of the N-O bond of the cycloadduct. This tandem nitroso Diels-Alder/retro hetero-Michael sequence has been used with cyclic and acyclic 1,3-dienes.
Calvet
Géraldine
G
Laboratoire de Synthèse des Substances Naturelles, Institut de Chimie Moléculaire et des Matériaux d'Orsay, Batiment 410, Université Paris Sud, 91400 Orsay-France.
Dussaussois
Marion
M
Blanchard
Nicolas
N
Kouklovsky
Cyrille
C