Benzaldehyde

NaHCO₃ and Tris used in this experiment were all purchased from Yantai Shuangshuang Chemical Co., Ltd. Concentrated sulfuric acid (H₂SO₄, 98%) purchased from Baishi Reagent Company. Pyrrole, benzaldehyde, methanol, chloroform and propionic acid were purchased from Energy Chemical Reagent Company. The deionized water (18.25 m Ω) used in the experiment was prepared by ultra pure water mechanism in the laboratory. The other reagents were pure for analysis and were not further purified before their use, and all experiments were conducted at room temperature.

Hydrazine hydrate (98 %), benzaldehyde (98 %), and methanesulfonic acid (99 %) were purchased from Energy Chemical. 3‐(Diethylamino)phenol (97 %, Sigma–Aldrich Chemical Co.), phthalic anhydride (Tianjin Fuchen Chemical Reagents Factory), 2‐methylresorcinol (98 %, J&K Scientific Ltd.), isothiocyanato benzene (Adamas), sodium hypochlorite (Tianjin Fuyu Chemical Reagents Factory), and other materials for the synthesis were used without further purification. All chemicals used for the synthesis were of analytical grade. Methanol for analysis was of spectroscopy grade. Copper(II) perchlorate, sodium(I) perchlorate, lead(II) perchlorate trihydrate, cadmium(II) perchlorate hexahydrate, lithium(I) perchlorate, magnesium(II) perchlorate, cobalt(II) perchlorate, and iron(II) perchlorate hydrate were of reagent grade (RG) and were purchased from Alfa Aesar. Zinc(II) perchlorate hexahydrate (RG, Aladdin Chemical Co., Ltd.), barium(II) perchlorate (RG, Sigma–Aldrich Chemical Co.), and silver(I) perchlorate (analytical grade (AR), Energy Chemical) were obtained from the indicated vendors, and nickel(II) perchlorate hexahydrate and mercury(II) perchlorate trihydrate with purities above 99.0 % were purchased from Strem Chemicals, Inc.