Product use：Basic raw materials, organic intermediates, pharmaceutical intermediates
The synthesis process is as follows:
hydrogenchloride; zinc(II) chloride; water;
Reactants are commercially availlable.
To a stirred solution of anthracene (1.78 g, 10 mmol), anhydrous ZnCl2 (1.64 g, 12 mmol) and paraformaldehyde (1.50 g, 50 mmol) in dioxane (20 mL) was slowly added concentrated aqueous hydrochloric acid (40 mL) at room temperature. The resu lting mixture was gentle refluxed for 3 h and allowed to stand for 16 h at room temperature. The fine granular solid formed was separated by filtration and washed with H2O and dioxane. The crude product was recrystallized from toluene. 1.8 g of a yellowish solid was obtained (64.1 percent yield). 1H NMR (500 MHz, CDCl3): delta 8.40 (m, 4H), 7.62 (m, 4H), 5.61 ppm (s, 4H).