Silica-bonded 1,4-diaza-bicyclo[2.2.2]octane-sulfonic acid chloride catalyzed synthesis of spiropyran derivatives

Abstract

a b s t r a c tIn this research, a novel nanostructured heterogeneous catalyst, namely silica-bonded 1,4-diaza-bicyclo[2.2.2]octane-sulfonic acid chloride (SBDBSAC), as an acidic ionic liquid based on 1,4-diaza-bicyclo[2.2.2]octane ring bonded to silica has been prepared and fully characterized by several techniques such as fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermogravimetric (DTG), scanning electron microscope (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDX). The nanostructured catalyst has been suxessfully used as reusable nanostructured catalyst for green, simple and efficient synthesis of spiropyrans by the one-pot tandem Knoevenagel-Michael-cyclization reaction of isatin derivatives or acenaphthenquinone with barbituric acid derivatives, and 1,3-dicarbonyl compounds under aqueous media.

Engaging Isatins in Multicomponent Reactions (MCRs) – Easy Access to Structural Diversity

“…Fifteen spiropyran derivatives were prepared with excellent yields (87–95 %) in short reaction times (40‐90 minutes), using aqueous media under reflux conditions. The heterogeneous catalyst was successfully recycled over 5 runs [87] . Moreover, the magnetic properties of the first heterogeneous nanocatalyst makes it desirable as its recovery from the reaction medium is easily performed by using an external magnet.…”

An overview on recent advances in the synthesis of sulfonated organic materials, sulfonated silica materials, and sulfonated carbon materials and their catalytic applications in chemical processes

“…In another published article by this research group, silica-supported sulfonated 1,4-diazabicyclo[2.2.2]octane 71 was used for the one-pot tandem Knoevenagel–Michael cyclization reaction between isatin derivatives 32 or acenaphthenquinone ( 33 ), barbituric acid derivatives 73 , and 1,3-dicarbonyl compounds 20 to afford spiropyran derivatives 74 and 75 in aqueous media under reflux conditions ( Scheme 12 ) [ 56 ]. The particular features of these protocols are short reaction times, high reaction yields, mild reaction conditions, and diverse desired products.…”

γ‐Fe2O3@SiO2‐EC‐ZnII: A Magnetic Recyclable Nanocatalyst for the Synthesis of Spiro[indoline‐3, 9′‐xanthene]trione Derivatives in Aqueous Media

“…Therefore, it is not surprising that a considerable interest in the synthesis of spirooxindole (especially spiro[indoline‐3, 9′‐xanthene]trione) derivatives has been grown recently . Although, there are a few methods in the literature for the synthesis of spiro[indoline‐3, 9‐xanthene]trione derivatives from isatin and dimedone . During last few years, the sustainable development of synthetic methodologies (with less environmental hazards) as a great challenge for chemical and medicinal researches has been provided selective access to the elaborated scaffolds combined with molecular diversity and eco‐compatibility .…”