Reversible Rearrangements of Chlorophosphane‐Dichlorogermylene Ylides to Trichlorogermylphosphanes — Structure Determination of a Tetranuclear Bis(chlorophosphane)bis(trichlorogermylphosphane) Silver Bromide Complex

Chlorophosphanes RR'PCl ( 1a : R,R' = 1b : R = t Bu, R' = i Pr, 1c : R = i Pr, R' = Et 2 N, 1d : R = Et 2 N react with the dichlorogermylene dioxane complex 2 furnishing trichlorogermylphosphanes RR'PGeCl 3 4a–d . In the cases of 1c/4c and 1d/4d the insertion reaction remain incomplete; similarly, 4a always contains, shortly after isolation in pure state, small amounts of 1a that can be detected by NMR. A provided by the reaction of trichlorosilylphosphane t Bu(Et 2 N)PSiCl 3 ( 5d ) with GeCl 4 . The alkyl(dialkylamino) trichlorogermylphosphane 4d exists only in an equilibrium with chlorophosphane 1d , which coordinates GeCl 2 leading to the dichlorogermylene complex 3d . A 1:1 mixture of 4a with 1a is formed by the novel cleavage (“chlorogermylation”) of the P–P bond of tetraisopropyldiphosphane with germanium tetrachloride. Di‐ tert ‐butyl(trichlorogermyl)phosphane 4e (R, R' = t Bu) reacts with silver bromide providing a crystalline silver complex 7 . A structure determination by X‐ray diffraction reveals that 7 is [Ag 4 Br 4 ( t Bu 2 PCl) 2 ( t Bu 2 PGeCl 3 ) 2 ]. 2C 7 H 8 . Two of the Ag atoms of the cubane‐like (AgBr) 4 core of 7 are coordinated by chlorophosphane 1e , the other two by trichlorogermylphosphane 4e .