Pd-Biurea/MCM-41: As an efficient and recyclable nanocatalyst for one-pot three-component synthesis of dihydropyrano[3,2-c]chromene derivatives

One-pot multicomponent reactions (MCRs) have proved to be very powerful and efficient bond-forming tools in organic and medicinal chemistry in the context of green chemistry.1 Dihydropyrano[3,2-c]chromenes and their derivatives which have received significant attention due to their important biological and pharmacological properties, have been synthesized using the MCR system.2 Along with other reaction parameters, the nature of the catalyst plays a significant role in determining yield and general applicability. In literature, various catalysts are used for the one-pot synthesis of chromene derivatives. In continuation of our previous work,3 we report herein the application of Pd-Biurea/MCM-414 as a heterogeneous and easy recoverable catalyst in the eco-friendly synthesis of dihydropyrano[3,2-c]chromenes derivatives 5 via a one-pot three-component condensation of aromatic aldehydes 1 with malononitrile 2 and 4‐hydroxycoumarin 3 in excellent yields. The synthesized derivatives were also characterized by melting points, FT-IR,1H-NMR, 13C-NMR, and this nanocatalyst was characterized using FT-IR, TEM, and BET techniques

کلیدواژه ها:

Heterogeneous nanocatalyst ، Multicomponent reactions ، 4‐hydroxycoumarin ، Dihydropyrano[3 ، 2-c]chromenes ، MCM-41.