Syntheses and reactions of [2,n]paracyclophan-(n+ 7)-enes
Abstract
Routes are described for the preparation of the [2,n]paracyclophanenes (1) from the corresponding thia-[3,n]paracyclophanes (2); photocyclisation of the olefins (1; n 7) gives the bridged phenanthrenes (12); bromine in carbon tetrachloride gives predominantly the cis-dibromides (10) with increasing proportions of the trans-dibromides (11) as n increases.