THE MECHANISM OF STEREOSELECTIVITY IN THE CYCLOADDITION REACTIONS OF ALPHA-HYDROXY-ORTHO-QUINODIMETHANES WITH THE FUMARATE OF METHYL LACTATE AND MANDELATE
Jl. Charlton et S. Maddaford, THE MECHANISM OF STEREOSELECTIVITY IN THE CYCLOADDITION REACTIONS OF ALPHA-HYDROXY-ORTHO-QUINODIMETHANES WITH THE FUMARATE OF METHYL LACTATE AND MANDELATE, Canadian journal of chemistry, 71(6), 1993, pp. 827-833
The Diels-Alder cycloaddition reaction of the fumarate of methyl lacta
te or methyl mandelate with alpha-hydroxy-ortho-quinodimethane produce
s an unexpected exo product with very high asymmetric induction. Exper
iments and calculations have been carried out that show that the origi
n of the stereoselectivity in these reactions is related to hydrogen b
onding between the alpha-hydroxy-o-quinodimethane and the lactate or m
andelate group in the dienophile.