Reactivity of “Frustrated Lewis Pairs”: Three‐Component Reactions of Phosphines, a Borane, and Olefins

All or nothing: Sterically frustrated Lewis pairs of phosphines and the borane B(C6F5)3 exhibit unprecedented reactivity with olefins to afford both inter- and intramolecular alkanediyl-linked phosphonium borates (see picture; black C, pink F, green B, orange P). These reactions are all the more remarkable given that any pair of these reagents do not react while the combination of all three reagents results in product formation.