Abstract In the presence of zerovalent π-bis (benzene) chromium (0)(I), perfluoropropylene (II) was found to undergo oligomerization under very mild conditions to dimers (bp 46, M+, 300) and trimers (bp 100–102 C, M+-19, 431) in the ratio of 2.5–3.0 to 1. One mol of metal complex could catalyze the conversion of 50 mol of perfluoropropylene. On the basis of 19 F NMR, the structures of the dimers are III and IV in a ratio of ca. 80/20 and the trimers V and ...