Rapid Construction of Chemical Libraries

Combinatorial synthesis, in which molecules are constructed by combining several different components, serves as a very efficient way of constructing such chemical libraries. The use of different starting molecular units for each component can quickly lead to a large number of product molecules. Such libraries may contain a compound having a desired biological activity or physical property. For example, construction 

The combinatorial chemical library approach has caused a major cultural change in laboratory chemical research and chemists are now performing many reactions at a time using automated synthesizers. The effectiveness of this approach depends on how rapidly we create chemical libraries. Therefore, each reaction should be as fast as possible in order to achieve library synthesis in a highly time-efficient manner. 

In this context, click chemistry has been explored as a method for rapid synthesis of compound libraries. In click chemistry, compounds are rapidly synthesized through heteroatom links by a set of powerful, highly reliable, and selective reactions, such as Huisgen s 1,3-dipolar cycloaddition reactions. Click chemistry uses chemical building blocks with built-in high-energy content to drive a spontaneous and irreversible linkage reaction with appropriate complementary sites in other blocks. 

Recently, a great demand for fast chemical synthesis has emerged in the clinical field. Positron emission tomography (PET) is a medical imaging technique that produces a three-dimensional image or map of functional processes in the body. The common PET probes contain radionuclides such as F, and Rb, the lifetimes of which are very short, 

The most commonly used PET probe is F-fluorodeoxyglucose (FDG). The synthesis of F-FDG has been carried out as follows. In the first step, F-KF is produced by irradiation of O-water with 

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