Computational data for the charge and energetic analysis of carbonyl compounds

The standard textbook position is that an alkyl group attached to a carbonyl group is electron-donating, and a trihaloalkyl group is electron-withdrawing.The computational data herein show that this is not actually the case. The electronic effects do not align with this expectation, and are quite subtle.However, thermodynamic calculations of stability align fully with experimental reactivity data, so this necessitates a change in the textbook explanations used to present and teach this chemistry.There are calculations, including charge analysis (Hirshfeld, NPA) and free energies from which one can calculate free energy changes of representative reactions and to explore how they relate to the changes in charge within the molecule as a result of substitution.The dataset is organised in the following way:Charge analysis of ethane and propane - this allows the effect of a methyl group on an alkene to be explored without the complication of an electronegative oxygen atom.Comparison of the effect of methyl on carbocation and alkene - this allows resolution of the apparent inconsistency that a more substituted alkene is simultaneously more stable and yet more reactive.Charge and thermodynamic analysis of aldehydes and ketones - data that allow the electronic effects of alkyl and trihaloalkyl groups to be explored with respect to carbonyl groups.Charge and thermodynamic analysis of alkanes - data that allow the electronic effects of alkyl and trihaloalkyl groups to be explored with respect to alkanes. This provides a benchmark for the above data.Charge and thermodynamic analysis of hydrates - data that allow the electronic effects of alkyl and trihaloalkyl groups to be explored in hydrates. It is not sufficient to explore only one side of the reaction equation.Charge and thermodynamic analysis of alkoxides - data that allow the electronic effects of alkyl and trihaloalkyl groups to be explored in alkoxides, which are the products of addition of negatively charged nucleophiles to carbonyls.Additional structures to balance equations - when exploring selected reactions, additional structures (water, hydride) are needed to balance the chemical equations.Direct electron density subtractions - these data directly explore changes in electron density without 'compressing' the effects to a single value of atomic charge.Energies of NBO deletions - these calculations directly explore the energetic consequences of a given substituent.<br>