Greener Pathways to Organics and Nanomaterials:
Sustainable Applications of Magnetic Nano-Catalysts
Rajender S. Varma
Cincinnati, Ohio, USA; E-mail: rajvarma@hotmail.com
Sustainable synthetic activity involving alternate energy input, and greener reaction medium in
aqueous or solvent-free conditions will be summarized for heterocyclic compounds, cross coupling
reactions, and a variety of named organic reactions; 1 these reactions are catalyzed by basic water or
recyclable and reusable magnetic nano-catalysts in aqueous media using microwave (MW) irradiation.2
Vitamins B1, B2, C, and tea or coffee, beet juice and wine polyphenols which function both as
reducing and capping agents, provide extremely simple, one-pot, green synthetic methods to bulk
quantities of nanomaterials in water.3 Shape-controlled synthesis of noble nanostructures via MWassisted spontaneous reduction of noble metal salts using sugars will be presented. 3b MW cross-linking
reaction of poly (vinyl alcohol) (PVA) with metallic systems; bimetallic systems,3c and SWNT, MWNT, and
C-603d and the formation of biodegradable carboxymethylcellulose (CMC) composite films with noble
nanometals;3e,f and the shape-controlled bulk synthesis of Ag and Fe nanorods in poly (ethylene glycol)
will be described.3g MW hydrothermal process delivers magnetic nanoferrites 4 and micro-pine structured
catalysts are obtainable in water from readily available metal salts. 5 Sustainable route to nanoparticles
using polyphenols from winery waste,6a or biodiesel byproduct, glycerol6b,c and their applications in
catalysis,7,8 toxicity9 and environmental remediation10 will be highlighted.The approach attempts to fulfill
most of the Green Chemistry Principles in a comprehensive manner and aims to create sustainable
functional chemicals that may find diverse applications with extreme level of waste minimization.
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