Hexafluoroisopropanol dispersed into the nanoporous SBA-15 (HFIP/SBA-15) as a rapid, metal-free, highly reusable and suitable combined catalyst for domino cyclization process in chemoselective preparation of alkyl rhodanines

Hexafluoroisopropanol dispersed catalytically amount of SBA-15 (HFIP/SBA-15) with organic substrate was found to be an efficient, ultra-fast and waste-free approach for the synthesis of the biologically and pharmaceutically interesting alkyl rhodanines. The advantages of the present method are low catalyst loading, simple procedure, waste-free and direct synthetic entry to excellent yield of rhodanines, high reusability of the catalyst, and short reaction time. Also, the reaction can be performed without activation and modification of the substrates under the neutral conditions. The solid SBA-15 and HFIP could be recovered and reused for recycling. (C) 2013 Elsevier B.V. All rights reserved.