Synthese d'ynamines fonctionnalisees en β de la triple liaison et stereoselectivite de l'hydrolyse des cycloadduits formes avec la cyclopentenone et les lactones α-β insaturees
Ynamine 3 reacts with cyclopentenone and lactone by cycloaddition to afford adducts and the hydrolysis of which steroselectivity controlled. The presence of the alkoxy group in β position of the triple bond does not interfere neither with the process of cycloaddition nor the high stereoselectivity of the hydrolysis of cyclobutanone enamines annulated with a five or a six membered ring.
A cyclobutadiene—palladium complex, obtained by dimerization of an ynamine is described. The crystal structure of this compound shows, as salient feature, that the cyclobutadiene ring is not planar, but highlypuckered. Anti-bonding interactions have been suggested as an explanation for this puckering.