Synthesis and thermal decomposition studies of homo- and heteroleptic tin(iv) thiolates and dithiocarbamates: molecular precursors for tin sulfides

Abstract

The syntheses and X-ray structures of novel heteroleptic thiolate/dithiocarbamate derivatives (Et₂NCS₂)₂(RS)₂Sn (R = Cy, CH₂CF₃) have been examined and their thermal decompositions compared with those of selected tin(II) and tin(IV) dithiocarbamates. The heteroleptic species decompose to SnS by initial elimination of RSSR to afford (Et₂NCS₂)₂Sn and subsequent loss of [Et₂NC(S)]₂S. In contrast, (Et₂NCS₂)₄Sn decomposes via [(Et₂NCS₂)₂SnS]₂, whose structure has been determined, and finally to SnS₂ by sequential elimination of [Et₂NC(S)]₂S. The two families of compounds, (R₂NCS₂)₄Sn and (Et₂NCS₂)₂(RS)₂Sn, thus provide single-source materials for bulk SnS₂ and SnS, respectively, by virtue of their differing decomposition pathways. Preliminary CVD experiments with (Et₂NCS₂)₂(CyS)₂Sn are also reported.