RIDING THE TIGER - USING DEGENERACY TO TAME WILD RADICAL PROCESSES

Xanthates are convenient precursors of a variety of radicals that can be captured in an inter-or intramolecular fashion. Overall, the proces s involves rupture of the sulfide C-S bond and addition of the element s of the xanthate to the olefinic trap. The xanthate in the product ca n be reductively removed in some cases simply by heating in isopropano l with stoichiometric amounts of dilauroyl peroxide. A new radical all ylation reaction based on allyl sulfones has also been devised where, in a manner similar to that with xanthates, a number of degenerate ste ps force the reaction in the desired direction.