Untitled

Thecloso-[Sn9M(CO)3]4− Zintl Ion Clusters where M=Cr, Mo, W: Two Structural Isomers and Their Dynamic Behavior

“…More recently, we have shown that nido- Sn 9 4À reacts with [Nb(h-C 7 H 8 ) 2 ] to give [(h-C 7 H 8 )Nb(cyclo-Sn 6 )Nb(h-C 7 H 8 )] 2À that contains two-center two-electron bonds. [26] This complex and closo- [Sn 6 {Cr(CO) 5 } 6 ] 2À are static on the NMR timescale, [25] as expected, and show one-bond SnÀSn coupling constants significantly larger that those of nido- Sn 9 4À . [12,15] The first metallated Zintl ion, a Sn 9 4À ÀPt(PPh 3 ) x complex characterized by 119 Sn NMR spectroscopy, was detected by Rudolph and co-workers in a reaction between nido- Sn 9 4À and [Pt(PPh 3 ) 4 ].…”

“…Previous studies on the [(h-C 7 H 8 )Nb(cyclo-Sn 6 )Nb(h-C 7 H 8 )] 2À [26] and closo- [Sn 6 {Cr(CO) 5 } 6 ] 2À [25] ions showed static behavior as expected based on the rigid structure types. In contrast, the nido-Sn 9 4À ion is highly fluxional due to a lowenergy exchange process requiring little atomic reorganization (see Scheme 1).…”

“…[12,15,27] However, the one-bond couplings for 1 ± 3 are less than those of the static closo-Sn 6 2À ions of the [{M(CO) 5 } 6 Sn 6 ] 2À complexes ( 1 J( 119 Sn, 117 Sn) 1740 ± 1848 Hz) [25] and the [(h-C 7 H 8 )Nb-(cyclo-Sn 6 )Nb(h-C 7 H 8 )] 2À ion ( 1 J( 119 Sn, 117 Sn) 1975 Hz). [26] Further studies on these and other metallated polystannides are in progress.…”

“…In a subsequent publication, we will describe the dynamic behavior of the Rudolph complex and its subsequent Pt insertion product, [Sn 9 Pt 2 (PPh 3 )] 2À . [28] Herein we describe the synthesis, structures, properties, and solution dynamics of the closo-[Sn 9 M(CO) 3 ] 4À ions in which M Cr, Mo, W. The structure of one polymorph of closo- [Sn 9 Cr(CO) 3 ] 4À was previously communicated. [23] In this study, we describe a new isomeric form of the closo-[Sn 9 M(CO) 3 ] 4À structure in both the solid state and in solution.…”

The Controlled Oxidative Coupling of Ge94− Zintl Anions to a Linear Trimer [Ge9=Ge9=Ge9]6−

“…In these two cases the parent nine-atom Zintl clusters were also "undisturbed", but the ML n unit occupies a waist position rather than the capping position. Very few cases are concerning the disintegration of the parent Zintl clusters resulting in novel metal-stabilized polyhedrons, [NbSn 6 Nb] 2Ϫ [10], [Pt@Pb 12 ] 2Ϫ [11] and [MoPb 5 Mo] 4Ϫ [12], as reported recently. Such complexes are yet unknown for the lighter homologues such as Ge 9 4Ϫ .…”