Functional Molecular Crystals from the Arylation of a Halogenoplatinum Complex: Stimuli Responsiveness, Comproportionation, and π-Bridged Dimerization.

A chloroplatinum complex was arylated to obtain stimuli-responsive molecular crystals. The resulting arylplatinum complex showed polymorph-dependent emission, mechano- and thermochromic luminescence as well as comproportionation and π-bridged dimerization. Simple mixing of structurally similar arylplatinum complexes at room temperature resulted in the transfer of their aryl groups (comproportionation), which allowed their mechanochromic profiles to be tuned. We also found that recrystallization of the complex afforded a dimerized product in which two platinum ions are bridged by aryl groups resulting in a very short (3.0466(10) Å) Pt-Pt distance.