Enhancement of intramolecular excimer formation and photodimerization of anthrylmethyl α,ω-alkanedioates via hydrophobic interactions

摘要

The fluorescence spectra and photodimerization of anthrylmethyl α,ω-alkanedioates (A-M_n-A) both in organic and in aqueous organic mixed solvents have been studied. In aqueous organic mixed solvents strong intramolecular excimer emission is detected and the quantum yield for the intramolecular photodimerization is significantly greater than those in organic solvents. These observations suggest that hydrophobic interactions force A-M_n-A molecule to self-coil. The ratio of the head-to-head to head-to-tail products in the intramolecular photodimers of A-M_n-A depends on the length of the linking chain. This work presents a successful example of application of hydrophobic interactions to enhancement of large-ring formation.