Butyllithium	Tetraethyllead

Some of the most useful reagents in organic synthesis are the organomagnesium halides (RMgX). These compounds are the product of a reaction between magnesium metal and an organohalogen compound in a suitable solvent. An indirect synthesis was reported by François Barbier in 1899, however organomagnesium compounds are named after Barbiers student, Victor Grignard. Barbier had noted that a mixture of methyl iodide, methyl ketone and magnesium metal in diethyl ether produced a tertiary alcohol. Grignard devised a mechanism that had three different steps: (PTO)