Multigeneration reactions

When looking at multicomponent reactions we have to differentiate between multicomponent one-pot reactions, where the reactive components react to a product without giving rise to isolable intermediates, and multigeneration reactions, where the reactions proceed via intermediates which can be trapped and isolated. The two reaction schemes differ significantly in their scope and application for combinatorial organic synthesis as schematically depicted in Figures 1.8.5.1 and... 

This simple sketch already illustrates the implications of multicomponent one-pot and multigeneration reactions on the number and on the diversity of the products that can be generated. While one-pot reactions allow the parallel generation of products with a minimum amount of manipulations and vessel transfers, the multigeneration versions offer the benefit of having access to a larger number of compounds and core structures, which ultimately results in greater diversity of the produced compound collections. In Chapter 1.8.5.1 we will describe some of the most... 

The following examples illustrate the important differences between multicomponent one-pot reactions and multigeneration reactions. Many of the previously mentioned multicomponent one-pot reactions proceeded via intermediately formed imines. Instead of forming these imines in situ they can be synthesised separately and engaged in a whole range of reactions as schematically shown in Scheme 1.8.5.16. 

Indeed, most reaction sequences can be regarded as multigeneration reactions in which every reaction step generates a reactive species ready to undergo the next transformation. The perfection of this concept are the so-called tandem -, domino - or cascade -reactions in which the intermediates undergo the next transformation directly, i.e. without isolation or activation. Two examples will be discussed below to illustrate this concept. 

Applications of solution-phase multicomponent and multigeneration reactions... 

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