Multinuclear alkylene zinc (MAZ) compounds of the type EtZn-(R ''-Zn)(n)-Et (R '' = ethyl and propyl branched alkylene groups) were synthesized by a simple one-step procedure in nonpolar hydrocarbon solvents from alpha,omega-dienes (e.g., 1,7-octadiene or 1,9-decadiene) and diethylzinc using a bis(salicylaldiminato)-Zr(IV) complex, [(2-methylcyclohexyl)N=CH(2-O-C6H3-3,5-di-tert-butyl)](2)ZrMe2, as a catalyst. The MAZ serves as a divalent reversible chain-transfer agent for olefin polymerization, resulting in telechelic Zn-metalated polyolefins whose molecular weights are controllable over a wide range. The Zn-terminated telechelics serve as a polymer precursor for further reactions and can be converted into a variety of telechelic functionalized polyolefins is high yield.