Metal carbonyl chemistry. Part V. Reactions of fluoro-olefins with octacarbonyldicobalt

Abstract

Octacarbonyldicobalt reacts with the fluoro-olefins CF₂:CF₂, CF₂:CFCl, or CF₂:CFBr at 100° to give nonacarbonyl-(trifluoromethylcarbon)tricobalt, CF₃·CCo₃(CO)₉, in high yields. At lower temperatures, or with a shorter reaction time, tetrafluoroethylene gives mainly µ-tetrafluoroethylenebis(tetracarbonylcobalt), (OC)₄Co·CF₂·CF₂·Co(CO)₄, which rearranges quantitatively when heated in vacuo to form the novel compound, µ-tetrafluoroethylidene-µ-carbonyl-bis(tricarbonylcobalt), (OC)₃Co(CF·CF₃)(CO)Co(CO)₃. The mechanism of formation of CF₃·CCo₃(CO)₉ from tetrafluoroethylene is discussed in terms of these intermediate compounds.