Preface

The pioneers of modern chemistry built the foundations of inventing, making and changing the chemical products that play an essential role in modern achievements. Green chemistry deals with chemical methodologies and approaches that reduce the use of raw materials or by-products resulting from a chemical reaction in manufacturing, including solvents or catalysts generating hazardous materials that are dangerous to human health or harmful to the environment. The use of sustainable, environmentally friendly processes and new, green chemistry technologies has become the choice for many processes involved in chemical synthesis, nano synthesis, extraction techniques, environmental remediation, and energy.

In this book, researchers from all over the world provide insights into the importance of green chemistry in different ways. Chapter 1 by Endang Tri Wahyuni and Eko Sri Kunarti highlights various chemical analysis and pollutant removal methods that follow some of the 12 principles of green chemistry. In Chapter 2, Nikhat Farhana focuses on eco-friendly protocols that are replacing traditional methods of synthesis followed in chemistry to synthesize life-saving drugs, and preventing the outflow of industrial waste. Surbhi Dhadda et al., in Chapter 3, discuss how recyclable ionic liquids (ILs) catalyze ring closure reactions of chalcones to obtain several heterocyclic rings, including pyrazoles, pyrans, and pyrimidines under ultrasonification. Among the very important features of these reactions are their short routine, high yields, environment-friendliness, high functional group tolerance, formation of a single product, high atom economy, and the absence of a need for column purification. Chapter 4 by Biplob Borah and L. Raju Chowhan provides a critical overview of the application of mechano-chemical techniques for the synthesis of five- and six-membered heterocycles, as well as complex-fused heterocycles and spiro-heterocycles under organocatalytic conditions. Sigüenza et al. in Chapter 5 report on the oxidation of spirostanic steroidal alcohols to their carbonyl analogues using the hypervalent iodine (III)/TEMPO-4-N-acetoxyamine system. In Chapter 6 by Bilal Ahmad Mir and Suresh Rajamanickam, oxidative reactions facilitated by potassium persulphate (K2S2O8) in the absence of a metal catalyst are reviewed, together with the quick and environmentally friendly synthesis of novel chemical species.

Recently, TADF materials have been used as an alternative to metal photocatalysts. In Chapter 7, Rajamanickam and Patel summarize the use of low-cost, less toxic and greener TADF materials, particularly 4CzIPN, as photocatalysts for various radical-based organic transformation reactions. Pinto et al. describe opportunities to make a solution-based green synthesis of transition metal chalcogenides and different experimental planning and analysis techniques, such as the design of experiments, life cycle assessment, and machine learning, in Chapter 8. Ioana Stanciu, in Chapter 9, details the classification, types, and important applications of biomaterials for different everyday applications. Radiation-induced mutation

breeding, as reported by Puripunyavanich et al. in Chapter 10, is a remarkable method that can lead to genetic variations resulting in superior mutant cultivars with new and useful traits.

The fields of nanoscience and nanotechnology will continue to grow due to the numerous benefits for our daily lives, including in human health, food processing, environmental safety and device engineering. In Chapter 11, Haridas et al. describe the eco-friendly production of a high-performance supercapacitor electrode material using a combination of Fe2O3, gum acacia-derived porous carbon, and ball mill-synthesized graphene. Chapter 12 by Sarika Verma et al., highlights the various green methods of synthesis and discrete applications of inner transition compounds, including the fabrication of lanthanide-doped nanophosphors, rare-earth zirconates, metal oxide nanoparticles, nanocrystal-based photoluminescent materials doped with rare-earth ions, self-assembled nano-spherical dysprosium MOFs, and nucleotidebased lanthanide coordination polymers. In the final chapter, Guzmán et al. discuss the efficient eco-friendly in-situ synthesis of non-aggregated, quasi-spherical silver nanoparticles with an average size of 22.4± 13.2 nm using a mixture of ascorbic acid and citric acid at pH10.

Finally, we are grateful to Kumari Smita for her helpful comments on several chapters and her excellent support in the conceptualization of this book.

**Dr. Brajesh Kumar**

Department of Chemistry, TATA College, Kolhan University, Chaibasa, Jharkhand, India

#### **Alexis Debut**

Section 1

Green Chemistry -

Fundaments

Professor, Centro de Nanociencia y Nanotecnologia (CENCINAT), Universidad de las Fuerzas Armadas ESPE, Sangolqui, Ecuador Section 1
