Effect of Noncovalent Interactions on the Properties of α,ω-Bis(2-acetylphenoxy)alkanes Depending on the Size of the Polymethylene Linker

A number of α,ω-bis(2-acetylphenoxy)alkanes have been synthesized with a yield of 40–90% by alkylation of 2′-hydroxyacetophenone with α,ω-dihaloalkanes. The X-ray data had allowed to reveal an effect of the size of the polymethylene linker on the conformations of α,ω-bis(2-acetylphenoxy)alkanes, which affect the melting points and are manifested in the UV spectra. A hypothesis that the conformation of α,ω-bis(2-acetylphenoxy)alkanes is determined by noncovalent interactions has been made on the basis of quantum-chemical calculations. Evaluation of the selectivity of the reaction of α,ω-bis(2-acetylphenoxy)alkanes with the entire series of alkali metal ions has demonstrated that a increase in the size of the polymethylene linker along the homologous series leads to an increase in the selectivity of the reaction with sodium ions, when the linker contains an odd number of methylene groups and with sodium and potassium ions, when the linker contains an even number of methylene groups.