Spontaneous Isomerization of a Hydroxynaphthalene-Containing Spiropyran in Polar Solvents Enhanced by Hydrogen Bonding Interactions.

ABSTRACT: The synthesis of spiropyran dyes exhibiting solvent-driven isomerization even in the dark condition is an important subject for the design of optical materials. A conventional synthesis strategy involves the conjugation of indoline moieties with electron-deficient aromatic moieties. Herein, we report that a spiropyran conjugated with a hydroxynaphthalene moiety (1) is a new member exhibiting solvent-driven isomerization, even bearing an electron-donating -OH moiety. The dye exists as a colorless spirocyclic (SP) form in nonpolar media. It, however, shows a blue color in polar media, especially in aqueous media, due to the formation of ring-opened merocyanine (MC) forms, where the isomerization terminates in 10 s even at room temperature. The spontaneous SP → MC isomerization origina

SUBMITTER: Shiraishi Y 

PROVIDER: S-EPMC8717586 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature