Stannylated Polynorbornenes as New Reagents for a Clean Stille Reaction

New functionalized polynorbornenes have been obtained in good yields by vinylic copolymerization of norbornene with a (norbornenyl)Sn-Bu2Cl monomer, catalyzed by [Ni(C6F5)(2)(SbPh3)(2)]. Subsequent functionalization produces a wide variety of polymers with different -SnBu2R groups (R = aryl, vinyl, alkynyl). The polymers can be used as R-transfer reagents in Stille couplings, thereby providing easy workup and separation of the polymeric tin byproducts from the coupling products. Tin contents of around 0.05 wt% are found in the Stille products. The stannylated polymers can be recycled and reused with good efficiency.