INTERRELATIONS OF THE ENERGETICS OF AMIDES AND ALKENES: ENTHALPIES OF FORMATION OF N,N-DIMETHYL DERIVATIVES OF PIVALAMIDE, 1-ADAMANTYLCARBOXAMIDE AND BENZAMIDE, AND OF STYRENNE AND ITS α-, TRANS-β AND β,β-METHYLATED DERIVATIVES

Article abstract of DOI:10.1002/poc.610080105

The enthalpies of formation of the condensed phase and gaseous N,N-dimethyl derivatives of pivalamide, 1-adamantylcarboxamide and benzamide were determined by combustion calorimetry and the associated enthalpies of vaporization and sublimation.The enthalpies of formation of styrene and its α-, trans-β- and β,β-methylated derivatives were determined from measurements of their enthalpies of hydrogenation in dilute hydrocarbon solution.Strain and resonance effects of amides and alkenes are discussed in terms of the exo-/endothermicity of the following reactions: CH3CONH2(g)+RC(CH3)=CH2 -> (CH3)2C=CH2(g)+RCONH2(g), CH3CON(CH3)2(g)+RCH=C(CH3)2(g) -> CH3CH=C(CH3)2(g)+RCON(CH3)2(g) and in terms of the difference of enthalpies of formation of the isomeric (Z)- and (E)-RCH=CHCH3.