An environment-friendly methodology for the construction of diversified bicycloacenaphtho[1,2-d]imidazole-8-thione scaffolds using spinel NiFe 2 O 4 nanoparticles as a sustainable catalyst.

Herein, we successfully developed an easy access to bicycloacenaphtho[1,2-d]imidazole-8-thione by one-pot three-component MCRs of acenaphthoquinone, aryl or alkyl isothiocyanates and amines using environmentally benevolent and recyclable spinel NiFe 2 O 4 nanocatalyst in aqueous ethanol. A broad number of products have been synthesized with both EDGs and EWGs present in the ring which increases the diversity of the protocol. The NiFe 2 O 4 nanopowder has been synthesized and thoroughly characterized by powdered XRD, HRTEM, EDX, BET and ICP-AES analysis. The protocol to this bicyclic-heterocycle is noteworthy due to good to excellent yields, practical simplicity and high regioselectivity without any troublesome or hazardous by-products and its easy recovery and reusability of the catalyst. Spinel NiFe 2 O 4 NPs-catalysed synthesis of various bicycloacenaphtho[1,2-d]imidazole-8-thione scaffolds under mild and sustainable conditions.