ACTION OF POTASSIUM FLUORIDE AND DBU ON BETA-FLUORO-GAMMA,DELTA-UNSATURATED P-TOLUENESULFONATES - A CONVENIENT ROUTE TO CONJUGATED 2-FLUOROALKADIENES

Potassium fluoride reacts in triethyleneglycol (TEG) on beta-fluoro-ga mma,delta-unsaturated p-toluenesulfonates to give 2-fluoroalka-1,3-die nes (HOTs elimination) and the corresponding difluoroolefins (substitu tion of O-tosyl group by fluorine). S-N/E competition may be related t o the structure of the starting tosylate. However, the exclusive forma tion of conjugated 2-fluoroalkadienes may be realized by using DBU at room temperature instead of KF.