The self assembly of [2]- and [3]-rotaxanes by slippage

Abstract
Both a [2]- and a [3]-rotaxane have been synthesised in good yield by slippage at 55 °C in acetonitrile of bisparaphenylene-34-crown-10 over size-complementary stoppers on a dumbbell-shaped molecule containing two 4,4′-bipyridinium recognition sites.