4-isopropenyl-3-tosylmethyl pyrrolidines through radical cyclizations of 4-aza-1,6-dienes - An approach to kainic acids

The cyclofunctionalization of 4-aza-1,6-dienes 1 and 2 - bearing a prenyl chain - via the radical addition of PhSeTs (4) has been investigated as a potential route to 4-isopropenyl-3-tosylmethylpyrrolidines. Since the oxidative elimination of the resulting selenides afforded mainly the undesired olefinic regioisomer, an alternative pathway via the rearrangement of allylic sulfones 10-11, was applied and provided, in good yields, the target heterocycles; 12a,b are potential precursors of kainic adds.