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 = tBu, R' = iPr, 1c: R = iPr, R' = Et2N, 1d: R = Et2N react with the dichlorogermylene dioxane complex 2 furnishing trichlorogermylphosphanes RR'PGeCl3 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 tBu(Et2N)PSiCl3 (5d) with GeCl4. The alkyl(dialkylamino) trichlorogermylphosphane 4d exists only in an equilibrium with chlorophosphane 1d, which coordinates GeCl2 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' = tBu) reacts with silver bromide providing a crystalline silver complex 7. A structure determination by X‐ray diffraction reveals that 7 is [Ag4Br4(tBu2PCl)2(tBu2PGeCl3)2]. 2C7H8. 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.