Spontaneous Decomposition of an Extraordinarily Twisted and Trans‐Bent Fully‐Phosphanyl‐Substituted Digermene to an Unusual Ge^I Cluster

Abstract

Ditetrelenes R 2 E=ER 2 (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 R 2 E. We report the synthesis of the first fully phosphanyl-substituted digermene {(Mes) 2 P} 2 Ge=Ge{P(Mes) 2 } 2 (3, Mes = 2,4,6-Me 3 C 6 H 2 ), which adopts a highly unusual structure in the solid state, that is both strongly trans-bent and highly twisted. Variable-temperature 31 P{ 1 H} 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 Ge I cluster {(Mes) 2 P} 4 Ge 4 •5 CyMe (7).

Structures, Bonding Analyses and Reactivity of a Dicationic Digallene and Diindene Mimicking trans‐bent Ditetrylenes

“…Apparently, this may be caused by the 5s 2 electron pair having an increased non-bonding character compared to the 4s 2 pair in the digallene. Typically, isoelectronic digermenes (θ = 0-47°; [14,49] one example with θ = 75° [ 50] ) and distannenes (θ = 1-64°) [14,51] display more acute trans-bent angles than those found in [{M(dcpe)} 2 ] 2 + (M = Ga, In, respectively).…”

Strukturen, Bindungsanalyse und Reaktivität eines dikationischen Digallens und eines Diindens, die trans‐gefaltete Ditetrylene nachahmen

“…Dies könnte darauf zurückzuführen sein, dass das 5s 2 -Elektronenpaar im Vergleich zum 4s 2 -Paar im Digallen einen stärker nichtbindenden Charakter aufweist. Typischerweise findet man für die isoelektronischen Digermene mit θ = 0-47°[ 14,49] (ein Beispiel mit θ = 75° [ 50] ) und für die Distannene mit θ = 1-64°[ 14,51] kleinere trans-Faltungswinkel als die in [{M(dcpe)} 2 ] 2 + (M = Ga bzw. In).…”