Heat of Formation of the Grignard Reagent, CH₃Mgl: Ether

Abstract

EXPERIMENTAL determinations of carbon-metal and carbon-halogen bond dissociation energies have been investigated in this Department during the past few years^1–4. The first work undertaken was a calorimetric study of the formation and subsequent decomposition of a Grignard reagent. From (1) and (2), the heat of formation of the RI compound can be obtained: From Q_f(RI,g), and the corresponding R—H dissociation energy, the R—I bond dissociation energy can be found. Even if the absolute value of the heat of formation as given by (3) is doubtful (owing to uncertainty in the value assumed for Q_f(MgIOH)), the gradations in Q_f values for a series of RI compounds should be reliable.