Acidity enhancement of alpha-carbon of beta diketones via hydroxyl substituents: A density functional theory study

摘要

Density functional theory method and B3LYP/6-311++G(d,p) level of theory were used to determine the acidity of alpha-carbon in the hydroxyl derivatives of beta diketones in the gas phase. An investigation of acidity strength in the gas phase indicates that alpha-carbon of hydroxyl derivatives of beta diketones become stronger acids than the alpha-carbon of beta diketone itself as their conjugate bases gain more stability via both enolate and hydrogen bond formation. Natural bond orbital and quantum theory of atoms in molecules analyses also confirm the role of hydrogen bond interactions on increasing the acidity of alpha-carbon of hydroxyl derivatives of beta diketones.