Comparison of reactivity of C,N-chelated and Lappert’s stannylenes with trimethylsilylazide

Abstract

Two mixed amido-azido tin(IV) species bearing either C,N-chelating or bulky amido ligands were prepared by the reaction of the corresponding stannylene (e.g., Sn[N(SiMe3)2]2 (1) or (LCN)2Sn (2, LCN = 2-(N,N-dimethylaminomethyl)phenyl)) with Me3SiN3. Both products of the oxidative addition, Sn[N(SiMe3)2]3N3 (3) and (LCN)2Sn[N(SiMe3)2]N3 (5), respectively, were fully characterized by both multinuclear NMR spectroscopy and XRD analysis. Heating of a mixture of 2 and Me3SiN3 up to 100 °C lead to the formation of a novel dimeric species (LCN)2Sn(μ-NSiMe3)2Sn(LCN)2 (4), where the two tin atoms are bridged by two NSiMe3 ligands, thus forming a four-membered diazadistannacycle. DFT calculations were also carried out to support the proposed reaction mechanisms.