Liquid Bail is a powerful solvent and can be used in a variety of chemistry reactions. The presence of CaO, SiO2 and BAIL in corn cobs allows for the liquefaction of the cobs. The ionic liquids present in Bail can be used to synthesize 4-phenacylideneflavenes and benzothiazole.
Synthesis of 4-phenacylideneflavenes in the presence of CaO@SiO2@BAIL
In this study, the synthesis of 4-phenacylideneflavenes was achieved by using a CaO@SiO2@BIAL catalyst. The catalyst was synthesized using aqueous sol-gel chemistry. The starting silica gel was prepared using TEOS as a precursor. The main moderator of the hydrolysis and condensation rates was acetic acid, which also controlled the pH of the reaction. The reaction was conducted in a two-liter glass reactor. The silica precursor was added to 700 cm3 of water at 75 degC. The resulting slurry was hydrolyzed in this solution, followed by its peptization with 29.4 g of anhydrous acetic acid
The cation positions were calculated by using the Brown and Altermatt parameters and the Brese-O’Keeffe parameters. The cation positions were compared to the ideal values of 2 v.u., and they were found to be significantly different from the ideal values.
X-ray powder diffraction (EDS) mapping revealed the presence of a crystalline calcium phase before calcination. This phase disappears after the calcination step, while the crystalline calcite phase was only found in the calcined samples. The presence of a calcium-rich solution in the reaction system increased the surface area of the gel, while the acetate-based phase remained stable.
The CaO@SiO2@BAL catalyst can be used to synthesize organic compounds without using solvents. The catalyst is highly efficient, exhibiting high yields of the desired products. Furthermore, the catalyst can be recovered and reused. These features make it an attractive heterogeneous catalyst preparation process.
Synthesis of benzothiazole in the presence of CaO@SiO2@BAIL
A two-component reaction involving different aldehydes and 4-Chloro-3-amino benzoic acid yields benzothiazole derivatives. The catalyst, which is magnetically retrievable and loaded, can be reused up to five times without losing activity. The synthesized benzothiazole scaffolds were characterized by FT-IR, 13C NMR, and mass spectroscopy.
The Lewis acid and Bronsted catalysts showed very low catalytic activities. However, the BAIL gel had a significant rate increase. After 5.5 h at 130 degC, 98% of the desired product was obtained. These results suggest that optimal conditions are required for the synthesis of benzoxazole. In addition, room temperature conditions did not lead to the production of the desired product.
Synthesis of benzothiazole in a solvent-free environment using a bronsted acidic ionic liquid gel is an effective method to make organic compounds in the presence of TEOS without solvent. Using BAIL gel in this manner has the advantage of high yields of the desired products and the catalyst is easily recovered and reused. Moreover, it is a very attractive heterogeneous catalyst preparation method.
Benzothiazole is a representative heterocyclic compound containing the benzene and thiazole ring system. It has various biological activities, including anti-fungal, anti-viral, and anti-inflammatory.
