Cubyl Anion Formation and an Experimental Determination of the Acidity and C−H Bond Dissociation Energy of Cubane

Cubane (1) and its derivatives have been the subject of numerous investigations ever since Eaton’s synthesis of the parent compound in 1964.1,2 Kinetic measurements indicate that 1 is an unusually acidic alkane3 and that its carbon-hydrogen bond dissociation energy (BDE) is considerably greater than that for a typical tertiary C-H bond.4 The thermodynamic values for these quantities, however, are unknown. Cubane’s acidity along with the electron affinity of cubyl radical could be used to derive the homolytic C-H BDE via a thermodynamic cycle (eq 1).