In this contribution the preparation of higher, all trans configured oligomers of diisoalkyloxysubstituted divinylbenzenes (PV-oligomers) via metathesis polycondensation of the corresponding low oligomers (telomerization) is described. The main concern was with the selectivity of the telomerization process. In this context two highly active metathesis catalysts were investigated. Two 2,5-disubstituted divinylbenzene trimers (with isopentyloxy resp. isooctyloxy substituents) were used as feed component. The time dependent product distribution was determined by means of MALDI TOF mass spectrometry. Results reveal that the molybdenum complex Mo(NPhMe2)(neoPh)[OCMe(CF3)(2)](2) is much better suitable than the ruthenium based catalyst Ru(=CHPh)(PCy3)[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-yli dene]Cl-2. With the molybdenum alkylidene complex higher conversions and above all considerably higher average degrees of polymerization were obtained before "side reactions" (splitting of the internal double bonds) occur. (C) 2003 Elsevier B.V. All rights reserved.