Synthesis and Photochromism of Spirobenzopyrans and Spirobenzothiapyran Derivatives Bearing Monoazathiacrown Ethers and Noncyclic Analogues in the Presence of Metal Ions

Citations Over TimeTop 10% of 2002 papers

Abstract

Spirobenzopyrans bearing monoazathiacrown ethers and noncyclic analogues were synthesized, and their ion-responsive photochromism depending on the dual metal ion interaction with the crown ether and the phenolate anion moieties was examined using alkali and alkaline-earth metal ions, Ag(+), Tl(+), Pb(2+), Hg(2+), and Zn(2+). The prepared spirobenzopyrans showed a selective binding ability to Mg(2+) and Ag(+) with negative and positive photochromism, respectively. Among the metal ions, only Ag(+) facilitated photoisomerization to the corresponding merocyanine form. Depending on the ring size of the monoazathiacrown ether moieties, soft metal ions such as Hg(2+) and Ag(+) showed significant shifts in the UV-vis absorption spectra, while hard metal ions such as Mg(2+), Zn(2+), and Pb(2+) did not afford any meaningful shift. This result reflects that the monoazathiacrown ether and phenolate anion moieties prefer soft and hard metal ions, respectively. Therefore, the Mg(2+) and Ag(+) selectivities are mainly derived from the phenolate anion and monoazathiacrown ether moieties, respectively. On the other hand, a spirobenzothiapyran bearing 3,9-dithia-6-monoazaundecane showed a remarkable selectivity to Ag(+).

Related Papers

• → Synthesis, Photochromic Properties, and Crystal Structures of Salts Containing a Pyridinium-Fused Spiropyran: Positive and Negative Photochromism in the Solution and Solid State(2020)23 cited
• → Efficient Negative Photochromism by the Photoinduced Migration of Photochromic Merocyanine/Spiropyran in the Solid State(2021)26 cited
• → Ion-depended photochromism of oxadiazole containing spiropyrans(2019)10 cited
• Synthesis and photochromic behavior of spiropyran dyes(2005)
• → Fluorescent Properties of Polymer Systems with Negative Photochromism Based on Complexes of Spiropyran with Metal Ions(2021)3 cited