ABSTRACT
Catalytic activity and selectivity of nanosized catalysts (nanocatalysts) are highly dependent on size, the surface-to-volume ratio and morphology of these materials. Nanocatalysis (catalytic reactions using nanocatalysts) has been explored extensively and applied to numerous catalytic conversions, which played a vital role in both industrial setup as well as in academic research. This chapter deals with the application of nanosized noble metal particles in organic transformations. Historically, gold (Au) was not considered as a catalyst as it was predicted that its high ionization potential would result in a low molecular attraction towards any substance. However, lately, nanosized Au particles have been seen to exhibit unique catalytic properties. For example, Au nanoparticles (Au NPs) are highly selective towards oxidation reactions and hydrogenation reactions of alkene, diene and alkynes. Likewise, palladium (Pd)-based nanosized catalysts have been used extensively due to their applications in a multitude of reactions such as in carbon-based cross-coupling, hydrogenation (addition), esterification, oxidation, and reduction. In recent years, the interest in iridium (Ir)-based nanocatalysts is increasing due to their high activity, stability and selectivity under different reaction conditions. Platinum (Pt) NPs have potential applications in a variety of areas such as catalysis, pharmaceuticals and synthesis of materials with specialized properties. We discuss the organic transformations being catalysed by Au, Pd, Ir, Pt and Ag NPs in this chapter.
