Neutral and cationic hexanuclear rhenium phosphine clusters with mu(3)-(phosphido-chalcogenido), mu(3)-(arsenido-chalcogenido), and mu(3)-(imido or oxo-chalcogenido) hetero ligand shells

Reactions of dry THF/MeCN solutions of Ca[(Re6S6Cl2i)-Cl-i(Cl-a)(6)] with s ilylated derivatives E(SiMe3)(2) (E = PhAs, PSiMe3, HN, O, S) and addition of trialkylphosphine PPr3 afford in high yields and at room temperature eit her the neutral clusters [(Re6S6X2i)-X-i(PPr3)(6)(a)] (1: X = As, 2: X = P) or the ionic compounds [(Re6S6X2i)-X-i(PPr3)(6)(a)](2+).[Re6S6Cl8](2-) (3: X = NH, 4: X = 0, 5: X = S). The compounds 1-5 were characterised by X-ray crystal structure analysis. A di-substitution reaction occurs on the ((Re6 S6Cl2i)-Cl-i)(4+) cluster core, where the two inner mu(3)-chloro ligands Cl -i are substituted by X (X = As, P, NH, O, S) and all six terminal chloro l igands Cl-a are exchanged by terminal PPr3-ligands.