Towards a temperature-guided molecular switch: an unusual reversible low-temperature polymorphic phase transition in a conformationally locked environment†
Abstract
A conformationally locked tetraacetate undergoes, quite akin to a temperature-guided molecular switch, a reversible thermal switching between two polymorphic modifications; the room-temperature α-form converted at −4 °C to a low-temperature denser β-form, which displayed an unusual kinetic stability till 67 °C and transformed back to the α-form beyond this temperature.