Metathesis Reactions of the super-Prussian Blue Systems [(Me3Sn)3M(CN)6] (M=Co, Ir) with, inter alia, Tetrapropylammonium (and -phosphonium) Ions: Crystal Structures of [(nPr4P)(Me3Sn)2Co(CN)6·2H2O] and [(nPr4N)(Me3Sn)2Ir(CN)6·2H2O]

Tetrapropylammonium and -phosphonium ions, nPr4E+, react readily with the polymeric super-Prussian blue derivatives [(Me3Sn)3M(CN)6] (M=Co, Ir), which are built up of infinite [–M–CN–Sn–NC–] chains, affording the dimorphic supramolecular assembly [(nPr4E)(Me3Sn)2M(CN)6·2H2O]. All representatives of the latter type are devoid of any extended [–M–CN–Sn–NC–] backbones. The single-crystal X-ray structures of 1a-P (E=P; M=Co) and 3a (E=N; M=Ir) document new examples of either modification. While Me4N+ and Et4N+ ions do not form sufficiently insoluble, R4N+-containing assemblies, nBu4N+ and nPen4N+ give rise to similar (i.e., R4N:Me3Sn=1:2) products as nPr4N+. The slightly modified super-Prussian blue system [{Me2Sn(CH2)3SnMe2}1.5Co(CN)6], 4, reacts with nPr4NBr to yield the assembly [(nPr4N) {Me2Sn(CH2)3SnMe2}Co(CN)6·2H2O], 4a, the powder XRD and solid-state NMR spectra of which strongly resemble those of 3a (with two cis-oriented CNSn(Me3)OH2 ligands). In the absence of suitable single crystals, in particular in the case M=Ir, powder XRD- and multinuclear solid-state NMR results have been carefully examined in view of specific similarities with already established structural patterns. The unexpected dimorphism of 1a, which has been described most recently for M=Co, could now also be confirmed for M=Ir. The experimental results of the present study in total indicate that the superiority of coordinative NSn bonds over OSn bonds, in combination with O–H···NC hydrogen bridges, decreases, in the presence of R4E+ ions, stepwise with the size of R (i.e., from methyl to n-propyl) and of M (i.e., Co vs Ir).