“…At 353 K, 4 a has a half‐life of approximately 6 days. For comparison, the first C−F bond cleavage is fast and 4 a forms from 1 and hexafluoropropene within minutes at 298 K. A further reaction between 1 and 1,1,1,4,4,4‐hexafluoro‐2‐butene (10 equiv; HFO‐1336‐mzz) did not allow the isolation of a new organoaluminium compound but instead led to the formation of an s‐ trans isomer of 1,1,4,4‐tetrafluorobutadiene and 1‐F 2 . While the unambiguous assignment of this pathway will have to await a full mechanistic study, it appears that, in this case, the rate of the second C−F bond cleavage step is either similar to or faster than the first, possibly due to the ease of 1,3‐diene formation over allene formation, leading directly to the organic product.…”