Consecutive Transformations of Tetrafluoropropenes: Hydrogermylation and Catalytic C-F Activation Steps at a Lewis Acidic Aluminum Fluoride

Functionalization reactions of the refrigerants HFO-1234yf (2,3,3,3-tetrafluoropropene) and HFO-1234ze (1,3,3,3-tetrafluoropropene) were developed. The selectivity and reactivity towards CF3 groups of C-F activation reactions can be controlled by employing either a germane or a silane as the hydrogen source. Unique transformations were designed to accomplish consecutive hydrogermylation and C-F activation steps. This allowed for an unprecedented transformation of an olefinic C-F bond into a C-H bond by heterogeneous catalysis. These reactions are catalyzed by nanoscopic aluminum chlorofluoride (ACF) under very mild conditions.