Supported copper on a diamide–diacid-bridged PMO: an efficient hybrid catalyst for the cascade oxidation of benzyl alcohols/Knoevenagel condensation

Abstract

In this study, a novel periodic mesoporous organosilica (PMO) containing diamide–diacid bridges was conveniently prepared using ethylenediaminetetraacetic dianhydride to support Cu(ii) species and affording Cu@EDTAD-PMO nanoparticles efficiently.

Recent Developments in Knoevenagel Condensation Reaction: A Review

“…Cu@EDTAD-PMO (Cu(II) species on ethylenediaminetetraacetic dianhydried-bridged periodic mesoporous organosilica), which catalyzed the oxidation of benzyl alcohols into corresponding aldehydes followed by subsequent Knoevenagel condensation with malononitrile (one pot multistep synthesis or cascade synthesis), provided corresponding α,β-unsaturated nitriles using TBHP(tert-butyl hydro peroxide) as a green oxidant under mild reaction conditions as shown in Scheme 7. The current protocol had many advantages such as good selectivity of the product was obtained by using nano-ordered and reusable Cu@EDTAD-PMO catalyst [54]. Lulu Chen and group used first time sodium alginate as catalyst for Knoevenagel condensation of furfural with acetylacetone produced high quality fuel precursor (3-(furan 2-ylmethylene) pentane-2,4-dione with 86.47% yield) as shown in Scheme 9.…”

Sulfamic acid grafted to cross-linked chitosan by dendritic units: a bio-based, highly efficient and heterogeneous organocatalyst for green synthesis of 2,3-dihydroquinazoline derivatives

“…Compared to homogeneous catalytic systems, heterogeneous ones are much more efficient for multiple and continous use in the chemical synthesis. [65][66][67] Indeed, heterogeneous catalyst systems benet from easy removal, recovery and recycling of the catalyst compared to homogeneous catalysts. 68 Therefore, chitosan application as a new support material for heterogeneous catalysis is increasing.…”

l-Asparagine–EDTA–amide silica-coated MNPs: a highly efficient and nano-ordered multifunctional core–shell organocatalyst for green synthesis of 3,4-dihydropyrimidin-2(1H)-one compounds

“…In many previous reports, ethylenediaminetetraacetic acid (EDTA) has been used as an ion exchange and chelating agent for various metal ions, 93–95 but this compound has a good ability as an inexpensive and non-toxic cross-linker to make strong bonds with organic materials having nucleophilic centers. 96,97 On the other hand, l -asparagine is one of the 20 amino acids found in the cells of the human body and is essential for maintaining balance in the central nervous system. 98 l -Asparagine can act as a biocompatible precursor and key part of bifunctional organocatalytic systems due to its high natural abundance and cost-effectiveness with acidic and basic sites.…”