Reaction of a number of 1, 6-diene or enyne systems with TolSO2SePh, under free radical conditions, results in selenosulfonylation with concomitant C C bond formation, to give cyclised alkyl or vinyl sulfones containing the synthetically useful phenylselenyl functionality. Similar cyclisations are possible by using Ph2PH in place of TolSO2SePh, resulting in the formation of cyclic phosphine or vinyl phosphine products, although in these reactions the ...