Phosphanyl‐Substituted Tetrylenes and Ditetrelenes: Impact of Steric Bulk on Tetrylene/Ditetrelene Stability

Phosphorus‐substituted tetrylenes and ditetrelenes remain something of a rarity. The reaction between SnCl 2 and two equivalents of (Dep 2 P)Li at low temperature gave the bis(phosphanyl)stannylene {(Dep) 2 P} 2 Sn ( 4Sn ), although this compound decomposes in solution at room temperature (Dep = 2,6‐Et 2 C 6 H 3 ). Compound 4Sn is monomeric in the solid state and exhibits significant Sn…Ar contacts, which mitigate the electron deficiency of the Sn center. In contrast, the reaction between GeCl 2 (1,4‐dioxane) and two equivalents of (Tep 2 P)Li gave the digermene (Tep 2 P) 2 GeGe(PTep 2 ) 2 ( 5Ge ; Tep = 2,4,6‐Et 3 C 6 H 2 ). Compound 5Ge crystallizes as a strongly trans ‐bent and twisted digermene; however, in solution, variable‐temperature 31 P{ 1 H} and 1 H diffusion‐ordered NMR spectroscopy reveal a dynamic equilibrium between the germylene and digermene forms of 5Ge .