Glucose/dimethylurea (natural deep eutectic solvent) immobilized on Fe3O4 magnetic nanoparticles for the one-pot synthesis of tetrahydrobenzo[b]pyran derivatives

Tetrahydrobenzo[ b ]pyrans have been widely studied by chemists due to their medicinal properties. This study reports a cheap, simple, practical, and non-toxic method for the synthesis of tetrahydrobenzo[ b ]pyran derivatives from the reaction of aldehydes, malononitrile, and 1,3-dicarbonyl compounds (5,5-dimethyl-1,3-cyclohexanedione) using a magnetic nanocatalyst based on a natural deep eutectic solvent (Glucose:Dimethylurea) immobilized on Fe 3 O 4 nanoparticles. The synthesized magnetic nanocatalyst Fe 3 O 4 @(Glucose:Dimethylurea) was characterized using FT-IR, TEM, FE-SEM, MAP, EDX, and XRD analyses. The advantages of the method used in this study include the use of an inexpensive, readily available, and non-toxic catalyst that can be easily recovered and reused. The procedure offers straightforward product separation, a simple reaction protocol, and reduced environmental impact due to solvent-free reaction conditions. This catalyst affords excellent yields (80–98%) within short reaction time (10–25 min) under mild conditions and can be reused up to five consecutive cycles without any noticeable loss of catalytic activity. • Glucose/dimethylurea (natural deep eutectic solvent (immobilized on Fe 3 O 4 magnetic nanoparticles was employed as an efficient, low cost and green systems in these reactions. • The catalyst displayed recoverability and reusability without any significant loss of its activity. • The synthesis of new tetrahydrobenzo[ b ]pyran derivatives under green and environmentally friendly conditions. • The magnetic nanocatalyst were characterized according to FT-IR, TEM, FE-SEM, MAP, and EDX analyses.