Stereoselectivity in the homo-Diels–Alder reaction: effect of a remote 7-substituent on nickel-catalysed cycloadditions

Abstract

7-Substituted norbornadienes have been shown to undergo highly stereoselective homo-Diels–Alder reactions with a variety of dienophiles. Excellent exo/endo selectivity (always > 97:3) was observed when methyl vinyl ketone was used as dienophile. Increasing anti/syn selectivity (up to 95:5 when Y = OBu^t) was observed as the electronegativity of the 7-substituent increased.