A platinum(II) molecular hinge with motions visualized by phosphorescence changes.

With the rapidly growing exploration of artificial molecular machines and their applications, there is a strong demand to develop molecular machines that can have their motional states and configuration/conformation changes detectable by more sensitive and innovative methods. A visual artificial molecular hinge with phosphorescence behavior changes is designed and synthesized using square-planar cyclometalated platinum(II) complex and rigid aromatic alkynyl groups as the building blocks to construct the wings/flaps and axis, respectively. The molecular motions of this single molecular hinge and its reversible processes can be powered by both solvent and temperature changes. The rotary motion can be conveniently observed by the visual phosphorescence changes from deep-red to green emission in real time.