Fm. Cordero et al., UNPRECEDENTED REARRANGEMENT OF 5-BENZOYL SUBSTITUTED BICYCLIC ISOXAZOLIDINES TO DEHYDRO PYRROLIZIDIN-2-ONES AND INDOLIZIDIN-2-ONES, Journal of the Chemical Society, Chemical Communications, (9), 1994, pp. 1047-1048
5-Benzoyl substituted isoxazolidines 3, obtained by 1,3-dipolar cycloa
dditions of pyrroline N-oxide and tetrahydropyridine N-oxide to phenyl
vinyl ketone, undergo a rearrangement to dehydro 3-phenyl-pyrrolizidi
n-2-one and 3-phenylindolizidin-2-one catalysed by Al2O3; the rearrang
ement products undergo a Michael addition to a second molecule of phen
yl vinyl ketone.