Tin Zintl ions

Table 3 NMR data for the transition metal derivatives of Tin Zintl ions ...

Advances in techniques include sophisticated NMR methods, both in solution and the solid-state, and computational methods, and these, coupled with X-ray diffraction and other established methods, have been applied to the study of a wide variety of structures. Topics covered in the book include Sn(II) clusters, tin Zintl ions, Sn(II) heterobimetallic compounds, RsSn+ cations, stannylenes (R2Sn ), stannenes (R2Sn=SnR2 and R2Sn=CR2), stannynes (RSn=SnR), organotin oxide, carboxylate and sulfonate clusters, dendrimers and macrocycles, organotin polymers, Sh-tt interactions, unusual bondings and structures, and compounds with non-linear optical properties. 

The dynamic properties of these two complexes are perhaps the most surprising and interesting of the transition metal Zintl ion complexes. The clusters have markedly different structures but are both prolate in nature with several different Sn environments. The tin atoms at opposite ends of both structures are separated by nearly 9 A, but all 17 atoms are in fast intramolecular exchange on the NMR time scale. 

Chapman DJ, Sevov SC (2008) Tin-based organo-Zintl ions alkylation and alkenylation of Sng - Inorg Chem 47 6009-6013... 

There is a variety of compounds that have Si bound to transition metals in relatively simple molecules such as Si[Re(CO)5]4 or in clusters such as [Co9(/x8-Si)(CO)21]2 . Germanium, tin, and lead also form clusters such as [Co5Ge(CO)16], Co4Pb(CO)16(PR3)4, and [Fe4Pb(CO)16]2 metallated Zintl ions are found in anions such as [Sn4Cr(CO)5 6]2- and [Ge9(/a1o-Ge)Ni(PPh3)]2. 17 ... 

In addition, the reactivity of Zintl ion solntions with layered materials have been reported. Solntions of IQSng in enrednce graphite and Hffe the potassium is intercalated into the structure and tin metal is deposited on the edges of the layered... 

If electrons are added into the crystal structure, they lead to the breaking of the Sn-Sn bonds, each atom carrying an unshared electron pair, and ultimately to the formation of isolated anionic clusters with triangular faces (deltahedra), known as Zintl ions (e.g. 1 and 2 see Chapter 1.6). These compounds are diamagnetic and poor conductors. They can be prepared either by reduction of tin with an alkali metal or electrochemically, and are soluble in polar, basic solvents. For example, [Na+]4 [Sng]" " can be prepared from the reaction of tin with sodium in ethylenediamine, or in the presence of a crown ether to associate with the sodium cations. The most common structure is a nine-atom cluster 2. ... 

Deltahedral Zintl Ions of Tin Synthesis, Structure, and Reactivity... 

Negatively charged clusters of some of the p-metals and semimetals are also stable in solutions and can be crystallized from them as ionic molecular compounds. Known, at present, are a number of such ligand-free anionic clusters, called Zintl ions. Some examples are the clusters with general formulas PUy", Eg , Eg , aud Ej where Pn = P, As, Sb and E = Si, Ge, Sn, Pb. This chapter will limit its attention to the synthesis, structure, and functionalization of molecular anionic clusters of tin. Although both nine- and five-atom clusters are known (Figure 2.6.1), the focus will be predominantly on the nine-atom deltahedral clusters Sug and Sn which are the most readily prepared and most extensively studied species. 

The Zintl ions shown in Figure 13.12 are closo- or nido-clusters. The compounds Rb4Li2Sng and K4Li2Sng, which contain urac/j o-[Sn8] (Figure 13.13b), have been prepared by the direct fusion of tin metal with the respective alkali... 

Most, if not all, solids containing Zintl ions and sequestered alkali metal ions are infinitely stable in the absence of moisture and oxygen. Since the original report of the solid state structures of (crypt-Na+)2(Pbs ) and (crypt-Na )4(Sn9 ) in 1975, " the synthetic use of crypt has now produced compounds containing Zintl ions of germanium, tin, lead, arsenic, antimony, bismuth and tellurium. " ... 

Finally, it should be mentioned that Zintl ions have found a (still) limited application in the production of surface-modified materials. Certain organic polymers can be metallated efficiently in a non-electrochemical route employing Zintl ions of tin in en solution.Similarly, many anisotropic inorganic materials, for instance metal single-crystals and graphite, can be surface-metallated by use of Zintl ions. The surface reaction between Sng " and gold crystals has been studied by electron microscopy. 

A review of discrete and condensed homoatomic clusters of germanium, tin, and lead is presented in Section 5.7. These main group cluster compounds are usually called Zintl ions or Zintl phases in recognition of extensive studies of Zintl and coworkers in the 1930s." The science of nanoparticles with conducting and... 

---