Impacts of medium, substituents, and specific interactions with water on hydration of carbonyl compounds

Theoretical study on hydration of carbonyl compounds has been done at B3LYP/6-31++G** and MP2/6-31++G** levels. The variations in Delta G (hyd) and hydration constants are explored in terms of medium effect, substituent effect, and hydrogen bonding abilities of carbonyl compounds and their hydrated products. The dielectric of medium decreases the Delta G (hyd) values thereby favoring the process. The presence of electron-releasing substituents at the carbonyl carbon disfavors the hydration process, while that of electron-withdrawing substituents favor the process. Hydrogen bonding interactions stabilize the product to a larger extent than the carbonyl molecules, thereby favoring the hydration process. Linear correlation between the calculated log K (hyd) values and the experimental values is seen in case of specific interactions with water (R = 0.976) than in the case without those interactions (R = 0.955).