Introduction of a novel basic ionic liquid containing dual basic functional groups for the efficient synthesis of spiro-4H-pyrans

In this research the synthesis of 1,1,-(butane-1,4-diyl)bis(1,4-diazabicyclo[2.2.2]octan-1-ium) hydroxide as an effective basic ionic liquid containing dual basic functional groups is reported. After characterization using FT-IR, H-1 NMR,C-13 NMR and mass analyses, this reagent is efficiently used for promotion of the synthesis of spiro-4H-pyrans via one-pot three-component condensation through a domino Knoevenagel/Michael/cyclization sequence. The attractive features of this process are simple procedure, short reaction times, high yields, no column chromatographic separation, commercial availability of the starting materials and recyclability of the catalyst. (C) 2016 Elsevier B.V. All rights reserved.