Pd complexes with chelating diimine ligands promote cyclopolymerization of isopropylidene allyl(1-crotyl)malonate (I-1) to afford the polymer having trans-1,2-disubstitued five-membered ring and trimethylene spacer in every structural unit. The polymerization 1,6-dienes with Ionizer n-alkyl groups (1-2: 1,6-octadiene; I-3: I,6-nonadiene; 1-4: 1,6-decadiene) also produces the polymers with the five-membered rings located regularly along the linear polymer chain. The cyclopolymerization is applicable to the I,6-octadienes and I,6-nonadienes with barbituric acid group, sulfonamide group, and I,3-indandione group. The polymerization of the I,6-dienes with isopropyl, isobutyl, and 2-butyl group at a vinyl carbon affords the polymers which are composed of five-membered rings and the spacers with a methyl branch. The polymerization of I-1 to I-4 obeys first-order kinetics to the monomer concentration, and the observed rate constants decrease in the order I-2 > I-3 > I-4 7,approximate to I-1. Cyclopolymerization of 1-1 under an ethylene atmosphere yields the copolymer of ethylene and the functionalized diene. High reactivity of ethylene monomer for insertion, however, results in low content of the units derived from I (4%) and the presence of uncyclized diene units.