Basic Magnetic Nanoparticles as Efficient Catalysts for the Preparation of Naphthopyrane Derivatives

Abstract

Aminosilane-functionalised spinel ferrite oxide (Fe 2 O 3 ) magnetic nanoparticles have been synthesised and used as efficient heterogeneous base catalysts for the condensation of aromatic aldehydes with malonitrile and α (or β) naphthole via a three-component reaction under solvent-free conditions at 80 °C. Quantitative conversion of the reactants is achieved under mild conditions. Recovery of the catalyst is easily achieved by magnetic decantation. The supported catalyst is reused four times without significant degradation in catalytic activity. Naphthopyrans are polyfunctionalised benzopyran derivatives that have many biological and pharmacological properties.

Aminopropyl coated on magnetic Fe3O4and SBA-15 nanoparticles catalyzed mild preparation of chromeno[2,3-d]pyrimidines under ambient and solvent-free conditions

“…7 Research continues on these particles, which have applications in catalysis, drug delivery and imaging. 8 In continuation of our research on new synthetic methods in organic synthesis using green catalysts, [9][10][11][12] we developed the synthesis of chromeno [2,3-d]pyrimidine derivatives via pseudo four component condensation of salicylaldehydes, malononitrile and secondary amines (Scheme 1), by using 3-aminopropyltriethoxysilane coated on magnetic Fe 3 O 4 nanoparticles [APTES-MNPs] and 3-aminopropyltriethoxysilane coated on SBA-15 [APTES-(SBA-15)] (Fig. 1) as catalysts under mild, ambient, and solvent-free conditions.…”

Synthesis of an efficient MOF catalyst for the degradation of OPDs using TPA derived from PET waste bottles

“…An ideal catalyst for catalytic degradation should be stable under aqueous acid or alkaline conditions, have high porosity, be cost-effective, easy to apply and retrieve, and have other desirable properties 17 – 20 . The effectiveness of a catalytic method depends on factors such as selectivity, kinetics, fast mass transfer, strong host–guest interactions, high specific surface areas (SSA), low-cost preparation, flexible approach to their preparation, recyclability, reusability, etc.…”