Alkyl-imidazolium based organosilica supported Fe/porphyrin complex: As novel, highly efficient and reusable catalyst for the unsymmetrical Hantzsch reaction

Abstract

A noble alkyl-imidazolium ionic liquid based organosilica supported Fe/meso-tetrakis(4-sulfonatophenyl)porphyrin complex (ILOS@Fe/TSPP) is prepared, characterized and its catalytic efficiency is studied in the unsymmetrical Hantzsch reaction. The ILOS@Fe/TSPP was prepared by hydrolysis and co-condensation of 1,3-bis(3-trimethoxysilylpropyl)imidazolium chloride under acidic conditions followed by treatment with Fe/meso-tetrakis(4-sulfonatophenyl)porphyrin complex at ambient temperature. The material was characterized with TGA, EDX, SEM, TEM, XRD and DRIFT analyses. The ILOS@Fe/TSPP was successfully applied as powerful catalyst in the Hantzsch reaction for the preparation of a set of different derivatives of polyhydroquinolines in high to excellent yields. This catalyst was recovered and reused several times without important decrease in its activity. Furthermore, compared to the classical studies, this study consistently demonstrated the advantages of low catalyst loading, free-solvent media, short reaction times and simple purification of products.

Covalently anchored tertiary amine functionalized ionic liquid on silica coated nano-Fe3O4 as a novel, efficient and magnetically recoverable catalyst for the unsymmetrical Hantzsch reaction and Knoevenagel condensation

“…Interestingly, heteroaromatic aldehydes such as thiophene-2-carbaldehyde and furan-2-carbaldehyde ( Table 2, entries 14 and 15) also underwent these transformations well to afford the target products in excellent yields (86-90%). Furthermore, the aliphatic aldehyde, which is a usually less reactive substrate, 28 was smoothly converted to the corresponding product as well ( Table 2, entry 16). These results demonstrate that the designed catalyst BIL@MNP showed an excellent performance for the one-pot synthesis of polyhydroquinolines.…”

“…However, these procedures suffer from one or more drawbacks in terms of using volatile organic solvents, long reaction time, low yields, tedious product separation and catalyst recycling. To overcome these limitations, some attractive heterogeneous catalysts such as In-SiO 2 , 26 cellulose supported sulfamic acid, 27 ILOS@Fe/ TSPP, 28 V-TiO 2 , 29 SPPN polymer, 30 PdRuNi@GO, 31 boehmite-SSA, 32 nano-ZrO 2 -SO 3 H, 33 Fe 3 O 4 supported Cu and Ni complex 34,35 are applied in this regard. Although these reported methods show respective advantages and provide better improvements for the synthesis of the target molecules, there is still scope for improvement, particularly towards developing a milder and cleaner protocol without using precious metals and organic solvents.…”

A one-dimensional manganese(III)–porphyrin coordination polymer: crystal structure and photophysical properties

“…They have therefore become one of the most widely studied chemical systems and have attracted widespread attention. Because of the advantages of metalloporphyrins and porphyrins, such as easy syntheses and operations, singlet and triplet longevity, and dense light absorption and emission, they provide a very general preparation basis for a variety of materials with different applications in many physical and chemical disciplines, such as sensors (Geng et al, 2019;Esteves et al, 2018;Evyapan & Dunbar, 2016), catalysis (Tawil et al, 2019;Gangemi et al, 2017;Elhamifar et al, 2017), molecular sieves (Yao et al, 2019;Hou et al, 2014) and optoelectronics and solar cells (Samia et al, 2020;Baek et al, 2015;Pengxia et al, 2014;Yang, Lin et al, 2019).…”

Magnetic nanoporous MCM‐41 supported ionic liquid/palladium complex: An efficient nanocatalyst with high recoverability

“…According to aforementioned subjects, in continuous of our recent studies and due to the importance of supported catalytic systems in chemical processes, [44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59] herein for the first time a novel magnetic mesoporous MCM-41 type silica supported ionic liquid/palladium complex [Fe 3 O 4 @MCM@IL/Pd] with core-shell structure has been designed, prepared and characterized and its catalytic application was developed in the one-pot synthesis of pyrano [2,3-d]pyrimidine derivatives under green conditions (Scheme 1).…”