Copolymerization of carbon monoxide with exo-methylenecycloalkane and dienes: synthesis of functionalized aliphatic polyketones

Synthesis of functional aliphatic polyketones was achieved by co- and terpo lymerization of the strained exo-methylenecycloalkane, methylenecyclopropan e (MCP), and also the dienes 1,5-hexadiene, 1,7-octadiene and 1,6-heptadien -4-ol, with carbon monoxide and propene, using the dicationic palladium(II) phosphine complex [Pd(dppp) (NCCH3)(2)](BF4)(2) (I) (dppp is 1,3-bis(diphe nyl-phosphino) propane) as the catalyst precursor. The resulting MCP/CO cop olymer contains both ring-opened and cyclic microstructures. Ring-opening c opolymerization yields exo-methylene functionalized polyketone. In contrast to hexadiene/carbon monoxide copolymer (Hx/CO), no ring structures were ob served in the alternating octadiene/carbon monoxide (Oc/CO) and heptadien-4 -ol/carbon monoxide (Hp-ol/CO) copolymers. The remaining double bonds were left intact to yield polymers with olefinic functionalities in the side cha ins. (C) 2001 Society of Chemical Industry.