2-Trimethylsilylmethylenecyclopropane (=3) was synthesized by reaction of lithio methylenecyclopropane with TMSCl. The lithium salt of (=3) reacts with some electrophiles by α- or γ-attack depending on the nature of the electrophile. Whereas alkenylbromides 8 and 9 or alkinylbromide 10 give exclusively α-attack, benzaldehyde reacts with γ-alkylation.