Fast and scalable solvent-free access to Lappert's heavier tetrylenes E{N(SiMe3)2}2 (E = Ge, Sn, Pb) and ECl{N(SiMe3)2} (E = Ge, Sn)

Abstract

Iconic Lappert's heavier tetrylenes E{N(SiMe₃)₂}₂ (E = Ge (1), Sn (2), Pb (3)) have been efficiently prepared from GeCl₂·(1,4-dioxane), SnCl₂ or PbCl₂ and Li{N(SiMe₃)₂} via a completely solvent-free one-pot mechanochemical route followed by sublimation. This fast, high-yielding and scalable approach (2 has been prepared in a 100 mmol scale), which involves a small environmental footprint, represents a remarkable improvement over any synthetic route reported over the last five decades, being a so far rare example of the use of mechanochemistry in the realm of main group chemistry. This solventless route has been successfully extended to the preparation of other heavier tetrylenes, such as ECl{N(SiMe₃)₂} (E = Ge (4), Sn (5)).