Spontaneous Decomposition of an Extraordinarily Twisted and Trans‐Bent Fully‐Phosphanyl‐Substituted Digermene to an Unusual GeI Cluster.

Ditetrelenes R2E=ER2 (E=Si, Ge, Sn, Pb) substituted by multiple N/P/O/S‐donor groups are extremely rare due to their propensity to disaggregate into their tetrylene monomers R2E. We report the synthesis of the first fully phosphanyl‐substituted digermene {(Mes)2P}2Ge=Ge{P(Mes)2}2 (3, Mes=2,4,6‐Me3C6H2), which adopts a highly unusual structure in the solid state, that is both strongly trans‐bent and highly twisted. Variable‐temperature 31P{1H} NMR spectroscopy suggests that 3 persists in solution, but is subject to a dynamic equilibrium between two conformations, which have different geometries about the Ge=Ge bond (twisted/non‐twisted) due to a difference in the nature of their π‐stacking interactions. Compound 3 undergoes unprecedented, spontaneous decomposition in solution to give a unique GeI cluster {(Mes)2P}4Ge4⋅5 CyMe (7). [ABSTRACT FROM AUTHOR]