G2 ab Initio Calculations of Enthalpies of Hydrogenation, Isomerization, and Formation of C(3) Cyclic and Acyclic Ketones and Alcohols.
We report the ab initio G2 enthalpies of hydrogenation and isomerization (Delta(hyd)H and Delta(isom)H) in the gaseous state, at 298 K, of 8 C(3) cyclic and acyclic ketones and alcohols, including cyclopropenone, cyclopropenol, and allyl alcohol. Delta(hyd)H(298) and Delta(isom)H(298) are found from the differences in total energy (E(0)) of the participants in the hydrogenation and isomerization reactions. Combination of calculated Delta(hyd)H(298) and Delta(isom)H(298) with one experimental enthalpy of formation (Delta(f)H(298)) in the set yields Delta(f)H(298) of all the rest. Results lead to an estimate of 20.5 kcal mol(-)(1) for the resonance energy of cyclopropenone.
Rogers
Donald W.
DW
Chemistry Department, The Brooklyn Center, Long Island University, Brooklyn, New York 11201.
McLafferty
Frank J.
FJ
Podosenin
Andrew V.
AV