The host compound 9-(4-methoxyphenyl)-9H-xanthen-9-ol (H) forms inclusion compounds with the solid guests 1-naphthylamine, 8-hydroxyquinoline, triethylenediamine and acridine. All four structures were successfully solved in the triclinic spacegroup P. Similar packing motifs arise for the 1-naphthylamine and the 8-hydroxyquinoline inclusion compounds where the main interaction is of the form (host)–OH⋯O–(host). Both the triethylenediamine and the acridine guests hydrogen bond to the host molecule. The thermal stabilities and kinetics of the solid–solid reactions were determined.