Levofloxacin, a chiral carboxycinolone, is a synthetic antibiotic with a broad spectrum effects. One of the challenges in the synthesis of this compound is efficient catalytic synthesis of their key structural intermediates (Q-acid). Several methods have been reported for the synthesis of this active pharmaceutical ingredient in which toxic and expensive solvents have been used. In this study, focusing on the last step in the synthesis of levofloxacin using commercial Q-acid, an attempt was made using catalysts with Lewis acid character and the use of safe solvents. First, magnetic montmorillonite (MM) was synthesized and purified. The reaction of methylpiperazine with Q-acid intermediate for levofloxacin synthesis was also performed under different conditions. The best results were obtained using methylpiperazine and Q-acid with a molar ratio of 1. 2: 1 in the presence of catalytic amounts of MM in ethanol solvent (95%) at 70 ° C for 8 h. At the end of the reaction, MM was recovered using a magnet and a simple filtration and dried for 2 h at 100° C for activation and used for 5 consecutive reactions to evaluate levofloxacin synthesis without significant decrease in efficiency. In total, taking into account factors such as raw material consumption, solvent type and simple recycling conditions, operating temperature and energy consumption, type and amount of catalyst and its recovery, solvent and catalyst biocompatibility, production of levofloxacin hemihydrate in the method presented in this study, are associated with lower cost, and its production at increased scales will have good economic benefits.

Some derivatives of nitroenamines were synthesized in moderate to good yields in the presence of sulfonic acid supported on silica-modified maghemite (g-Fe2O3@SiO2–OSO3H) as a highly efficient and magnetically separable catalyst. Both up to five times recyclability and the magnetic separation are salient features of this catalytic system.

In this paper, HZSM5 zeolite was synthesized through reflux method on support material CaO (25, 35 and 45 wt%) in two specific methods: microwave and impregnation at high temperature. The zeolite catalyst was modified with impregnation of NaOH (2, 4, 8, 12 wt%) at room temperature. The modified zeolite was used in transesterification of rapeseed oil with methanol in abatch catalytic process. In transesterification of rapeseed oil, the catalyticactivities of HZSM5, NaZSM5, KZSM5 were considered. The prepared catalysts were characterized by several techniques such as X-ray diffraction (XRD), Brunauer Emmett Teller (BET) surface area and also the surface image was scanned by scanning electron microscopy (SEM). The parameters affecting on biodiesel yield at optimum reaction conditions were investigated. The maximum yield was achieved with 8wt% of NaOH loaded on HZSM5 at reaction temperature of 65˚ C, reaction time of 12 hours and catalyst/oil mass ratio of 9. Also the yield of CaO loaded with impregnation at high temperature was more desired than CaO loaded with microwave. Meanwhile the catalytic activity of HZSM5, NaZSM5 and KZSM5 was nearly zero; and the catalytic activity of modified zeolite was HZSM5>NaZSM5>KZSM5 subsequently.

Using magnetic and recyclable catalysts to promote selective C– C bond formation could help in the design of safer and ‘ ‘ greener’ ’ chemical manufacturing process. This work describes the preparation of magneto Ni(II) complex (Fe3O4@PCAPic/NiII) as a novel semi-Heterogeneous system and the evaluation of their potential catalytic activity towards the Henry (nitroaldol) reaction between nitroethane and a variety of aldehydes in aqueous medium. The morphology and structural feature of the catalyst were characterized using different microscopic and spectroscopic techniques such as FT-IR, UV-Vis, TGA, SEM, TEM, ICP, XRD, XPS, and VSM. The Fe3O4@PCA-Pic/NiII represented perfect catalytic efficiency and good diastereoselectivity for the nitroaldol reaction. Other notable advantages of this work include high stability and reusability of the catalyst, green reaction conditions, ease of separation of products, and cost-effectiveness. Also, this catalyst can be recycled by applying an external magnetic field and reused up to ten runs without significant loss of activity.