Green synthesis of novel 1,3-oxazine-2-thiones using NiFe2O4@amino glucosyl-SiO2 as a recyclable catalyst

The synthesis of 1,3-oxazine-2-thiones has attracted attention in the past because of their potential as antibiotics, antitumor, analgesics and anticonvulsants. One present significant area of new synthetic chemistry is the expansion of effective workable procedures that diminish the necessary reagents, solvents, cost time and separation courses for the preferred conversion and also minimize the creation of waste.1,2 Multi-component reactions (MCRs) are powerful tools in modern medicinal chemistry, enabling straightforward access to large libraries of structurally related, drug-like compounds and thereby facilitating the generation of lead candidates compounds. Hence, combined with the use of combinatorial chemistry and high throughput parallel synthesis, such reactions have constituted an increasingly valuable approach to drug discovery efforts in recent years. On the other hand, nanostructures as efficient catalysts have been used in various organic catalytic reactions. Among the numerous metal oxides, Fe3O4 and NiFe2O4 have attracted most interest due to its special properties. Although iron oxide particles surface exhibits both Lewis acid and base properties, the nature of metal cation and surface area of the metal oxides have extensively amplified their catalytic properties. The reactivity of Fe3O4 and NiFe2O4 has been shown to increase greatly as their dimensions are reduced and they may undergo rapid biodegradation when exposed directly to biological systems. Suitable coating is essential to prevent such limitation. 3,4 In continuation of our research for the green synthesis of organic compounds, 3-6 we describe here synthesis and the use of acidic amino glucose‐functionalized silica‐coated NiFe2O4 nanoparticles (NiFe2O4@amino glucosyl-SiO2) as a green, reusable and effective nano catalyst for the synthesis of 1,3-oxazine-2-thiones (Scheme 1). The structures of the synthesized 1,3-oxazine-2-thiones were confirmed by 1H, 13C NMR and FT-IR spectral data and elemental analyses.

کلیدواژه ها:

Oxazine ، Synthesis ، Green reaction ، Nano catalyst