COMPOSTOSORGANOMETÁLICOS DEESTANHO(II) –ESTANILAS DEALGUNSMETAIS REPRESENTATIVOS

ORGANOMETALLIC COMPOUNDS OF TIN(II) - SOME MAIN GROUP METAL STANNYLS. This paper aims to summarise some chemical information about selected main group metal stannyl compounds. The number of these compounds in the literature are much fewer than those with transition metal cations. Most papers report details of stannyls containing Li(I), Na(I) and K(I), such as synthetic routes, spectroscopic results and their molecular structures. This review comprises not only information of stannyls containing these cations, but also some alkaline-earth species containing Mg(II), Ca(II), Sr(II), Ba(II), as well as Sn(II). In some compounds, the alkaline or alkaline earth cation is connected to the stannyl fragment through a Sn – M bond, evidenced by X-ray crystallographic data or by solution- or solid-state 119Sn NMR experiments. The introduction part of the paper summarizes the chemical aspects of these compounds and their importance in the organometallic chemistry of Sn(II) as a research area. The second part of this review is dedicated to a broad discussion of the syntheses and structural aspects of some Li(I), Na(I) and K(I) derivatives. The structure of some stannyl compounds of Mg(II), Ca(II), Sr(II), Ba(II) are displayed in the third part of this paper. Two rare examples of Sn(II)-based stannyl derivatives are shown in the final part of the review. This review also highlights how important it is to correlate X-ray crystallographic data with those obtained by solution- or solid-state 119Sn-NMR experiments in order to determine the degree of covalence in the Sn – M bond.