**2. Green aspects of click reactions**

According to Sir John Cornforth, a Noble Prize laureate in chemistry in 1975, ideal reaction has been defined as "The ideal chemical process is that which a onearmed operator can perform by pouring the reactants into a bath-tub and collecting the pure product from the drain hole" [16]. Click reactions are designed in such a way that it involves all the twelve principles of green chemistry. Click chemistry includes synthetic methods that are designed to maximize the inclusion of all resources used in the process into the final product. Due to involvement of addition and rearrangement reactions, they have high atom economy. The products are designed with maximum efficacy and minimum cytotoxicity [17]. The green aspects have been depicted in **Figure 1**.

**Figure 1.** *Green aspects of click chemistry.*

condition, high yield, good atom economy, avoid toxic catalyst and solvent, and so on. They encompass reactions that are high yielding, fast, modular, and wide in scope. They are practical and tolerant for a variety of functional groups. Finally, the product isolation is expected to be effortless due to lack of by-products. These vast characteristics make click chemistry a powerful tool that paves a path in several fields of research *viz.* designing of drugs and lead structures [1–4]. Therefore the synergy between these disciplines has given rise to an area of intense research activity. The click chemistry has been such an engrossing topic of research that a lot of review articles have been published so far which explained its applicability in various fields of chemistry like manufacturing and alteration of metal–organic frameworks [5], making devices in bio-sensing system for responsive copper identification [6], designing bio-adhesives for hastening wound closure [7], in virusrelated research [8], generation of biosensors [9], proteomics analysis [10], in strategy for indirect 18F-labeling [11], *in vivo* bio-imaging [12], to identify the interaction of curcumin with protein [13], synthesis of polymers and material science [14], for surface modification [15], and so on. In this chapter, the state-ofart modernization with a particular focus on click chemistry assisted synthesis and their uses in various fields of science have been discussed. An attempt has been done to prepare an outline of the importance of click chemistry and its foremost requirement in the research area. It is predicted that this methodical study will pave the way for future opportunities in this direction and design of safer, economical,

*Current Topics in Chirality - From Chemistry to Biology*

According to Sir John Cornforth, a Noble Prize laureate in chemistry in 1975, ideal reaction has been defined as "The ideal chemical process is that which a onearmed operator can perform by pouring the reactants into a bath-tub and collecting the pure product from the drain hole" [16]. Click reactions are designed in such a way that it involves all the twelve principles of green chemistry. Click chemistry includes synthetic methods that are designed to maximize the inclusion of all resources used in the process into the final product. Due to involvement of addition and rearrangement reactions, they have high atom economy. The products are designed with maximum efficacy and minimum cytotoxicity [17]. The green

and eco-friendly pathways.

**2. Green aspects of click reactions**

aspects have been depicted in **Figure 1**.

**Figure 1.**

**66**

*Green aspects of click chemistry.*
