Investigations into the small-bite N-functionalised amido chemistry of silicon and tin(IV)

Treatment of [(APyTMS)Li(OEt2)], (APyTMSH=6-methyl-2-(trimethylsilylamino)-pyridine) with one equivalent of SiCl4 affords [SiCl3(APyTMS)], while similar treatment of [(APyTMS)Li(OEt2)] with 0.5 equivs of SiCl4 or SnCl4 yields [SiCl2(APyTMS)2] and [SnCl2(APyTMS)2], respectively, in good yield. [SiMe2(APyH)2] is obtained by treating [(APyH)Li(OEt2)] with 0.5 equivs of Cl2SiMe2. All complexes were characterised by NMR and IR spectroscopy, and in the case of [SiCl3(APyTMS)] and [SnCl2(APyTMS)2] by X-ray crystallographic methods. The X-ray structure of [SiCl3(APyTMS)] reveals a mononuclear compound with a hypervalent five-coordinate silicon centre, while [SnCl2(APyTMS)2] is mononuclear with a distorted octahedral tin(IV) centre.