Enthalpies of Formation of Globular Molecules. I. Adamantane and Hexamethylenetetramine

Abstract

Enthalpies of combustion at 298.15°K have been measured for crystalline adamantane (tricyclo-[3.3.1.13,7]decane) and hexamethylenetetramine (1,3,5,7-tetraazatricyclo[3.3.1.13,7]decane). The derived enthalpies of formation for the two compounds in the crystalline state, ΔHt°(c), at 298.15°K are –47.14 ± 0.19 and +29.65 ± 0.18 kcal/mol, respectively. Use of adjuvant data for both compounds permits evaluation of corresponding enthalpy values, ΔHf°(g), at 298,15°K for the gaseous compounds as –32.96 ± 0.19 and 47.6 ± 0.7 kcal/mol. The strain energies of both compounds are discussed. © 1970, American Chemical Society. All rights reserved.