Abstract
The Pd-catalyzed coupling of 1,5-diene-2-yl triflates with amine nucleophiles affords exomethylenecyclobutanes bearing dialkylaminomethyl groups at C2. The strained carbocyclic products are obtained in moderate to excellent yields, with regioselectivities of up to >95:5 for four-membered ring formation. The mechanism of these reactions, which provides products resulting from anti-addition to alkenes, differs from related reactions involving malonate nucleophiles that provide syn-addition products.