A tribute to Frederick Nye Tebbe. Lewis acid stabilized alkylidyne, alkylidene, and imides of 3d early transition metals

Frederick Nye Tebbe distanced himself from the spotlight despite increasing appreciation of his discoveries by the scientific world. Although his research accomplishments are numerous and significant, perhaps his most highly recognized contribution is the reagent that bears his name, Cp₂Ti(μ₂-CH₂)(μ₂-Cl)Al(CH₃)₂: an inspiring molecule to the area of olefin metathesis and methylidene transfer. Masking its potential via Lewis acid stabilization, Tebbe tamed the titanium methylidene moiety, leading many other scientists to exploit the wide-ranging reactivity of such a unit, including olefin metathesis, methylenation, and metallacyclobutane formation, among others. In this perspective, we pay tribute to the life and chemistry of the man behind the masked methylidene and the research progeny spawned by his discovery, focusing on the Lewis acid stabilization of multiply-bonded ligands of the early metals such as Sc and Ti.