Neighbouring group participation in N-Methoxymethyl 7-Azanorbornanes 1

A new tandem route to N,N′-methano-bridged diazasesquinorbornanes is reported in which 7-azabenzonorbornadienes are reacted with ester-activated N-(methoxymethyl)aziridinocyclobutanes to form adducts which immediately undergo N,N′-methanobridge formation by nucleophilic attack of the nitrogen lone pair of one N-bridge onto the methoxymethyl group attached to the adjacent N-bridge. Alternative routes to N,N′-methano-bridged structures of this type are discussed.