The first mixed phosphatetrahedranes were reported only recently and their reactivity is virtually unexplored. Here we present a reactivity study on di‐ tert ‐butyldiphosphatetrahedrane ( 1 ), which is the dimer of tert ‐butylphosphaalkyne. The ( t BuCP) 2 tetrahedron is activated selectively by N‐heterocyclic carbene (NHC) nickel(I) and nickel(0) complexes, resulting in novel complexes featuring diverse ( t BuCP) n ‐frameworks ( n = 2, 4). Release of the ( t BuCP) 4 framework from one of the complexes was achieved by addition of CO gas. Furthermore, 1 can be used as a source for P 2 units by elimination of bis‐ tert ‐butylacetylene in the coordination sphere of nickel.