Stille cross-coupling reaction of polyfluorovinylstannanes: Stereospecific synthesis of polyfluoro-alkenes and -α,β-unsaturated ketones

The palladium/copper (I) iodide cocatalyzed coupling reaction of (Z)-α-fluoro-β-trifluoromethylvinylstannanes 1 with aryl iodides 2 and acid chloride 4 has been explored affording substituted (E)-α-fluoro-β-trifluoromethylalkenes 3 and (E)-α-fluoro-β-trifluoromethyl-α,β-unsaturated ketones 5, respectively. The effect of cocatalyst, solvent as well as reaction temperature has been investigated in more detail. The geometric isomers were easily ascertained on the basis of their coupling constant (4JFF) across the double bond and the retention of the configuration of the products for this conversion was found.