Control by one drop of solvent: selective preparation of guest release/trap-triggered interconvertible molecular crystals

Abstract

Interconvertible molecular crystals 1_close and 1_open composed of 4-pyridyl-1,3-indanedione dimer 1 were selectively obtained. Thermal removal of solvent molecules in 1_open afforded 1_close. Further dipping of 1_close in a specific solvent reproduced 1_open. No crystallinity loss was observed even though both processes involved a drastic change of molecular packing arrangements.