General Concept of Multicomponent Reactions

Multicomponent reactions represent a flexible tool for the synthesis of a large number of target molecules from three or more starting molecules. They are one-step, one-pot reactions, economic regarding resotrrces and today considered to be close to what is defined as ideal synthesis [1]. Their general synthetic value was recognized when I. Ugi and collaborators reported on some important variants of four-component reactions [2] and their application in the production of known drugs an illustrative example is presented in the next section. 

It is interesting that three multicomponent reactions were broadly used over 150 years, known as name reactions according to their inventors Strecker synthesis of amino acids [3], Hantsch synthesis of 1,4-dihydropyrimidines [4] and particularly the imjxjrtant Mannich reaction [5]. 

---