Brönsted acidic ionic liquid-catalyzed multicomponent synthesis of pyrano[c]chromenes

Multicomponent reactions (MCRs) have emerged as an efficient and powerful tool in modern organic chemistry towards the generation of highly diverse and complex product from readily available substrates in a single operation without isolation of intermediates in minimal time with maximum selectivity, high atom-economy and high purity with excellent yields. MCRs have an outstanding status in medicinal chemistry and modern organic synthesis because they are one-pot processes that assemble three or more components. 1, 2Dihydropyrano[c]chromenes and their derivatives are of considerable interest as they possess a wide range of biological properties such as diuretic, analgesic, myorelaxant, anticoagulant, anticancer, anti-tumor, cytotoxicity and anti-HIV activities. They are also used as antimicrobial and anti-tuberculosis agents. 3-5In this study we have investigated the catalytic activity of a Brönsted acidic ionic liquid, [DABCO](SO3H)2(Cl)2, in the synthesis of annulated pyrano[c]chromene derivatives to introduce a time- and cost-saving method using a recyclable catalyst (Fig 1).

Keywords:

Multicomponent reaction , [DABCO](SO3H)2(Cl)2 , Brönsted acidic Ionic liquid , Pyrano[c]chromenes.