Establishing trends based on solvent system changes in cocrystals containing pyrogallol[4]arenes and fluorescent probes rhodamine B and pyronin Y

Abstract

Cocrystal systems containing pyrogallol[4]arene molecules of various aliphatic tail lengths, the fluorescent probe rhodamine B, and a variety of solvents are examined and discussed. Additionally, two pyronin Y cocrystals of C-methylpyrogallol[4]arene in methanol and C-ethylpyrogallol[4]arene in ethanol are crystallized and analyzed. For both the pyronin Y and rhodamine B cocrystals, solvent and aliphatic chain length have an effect on the packing, bowl shape of the pyrogallol[4]arene, probe complexation, and hydrogen bonding schemes. With pyronin Y cocrystals of C-methylpyrogallol[4]arene form a tube-like structure, with pyronin Y molecules in the centre of the tube while cocrystals of C-ethylpryogallol[4]arene form a bilayer-type structure.