Biomedical Engineering Reference
In-Depth Information
STRATEGIC APPLICATIONS OF
MULTICOMPONENT REACTIONS IN
DIVERSITY-ORIENTED SYNTHESIS
JOHN M. KNAPP, MARK J. KURTH, JARED T. SHAW, AND
ASHKAAN YOUNAI
2.1
INTRODUCTION
Multicomponent reactions (MCRs), chemical processes in which three or more
reagents react selectively to form a single product, are extremely efficient trans-
formations in organic synthesis. Although this concise definition will be adopted for
the purposes of this chapter, the reader is advised that the term MCR is not subject
to strict (e.g., mechanistic) delineation in the manner of reactions that are classi-
fied as catalytic or concerted. In the strictest sense, an MCR involves the admixture
of at least three chemicals without regard to precise control of the order of addi-
tion and with the further restriction that each component be variable. As such, a
three-component reaction (3CR) should involve three reagents, each of which can be
structurally varied. Examples of commonly occurring variable components include
primary and secondary amines, ketones, aldehydes, carboxylic acids, and isonitriles.
In the most liberal definition, any series of reactions involving at least three reagents
in one reaction vessel that contributes to the final product structure might be referred
to as an MCR. This would include many tandem, “one-pot,” and cascade processes,
some of which amount to two separate reactions performed without isolation of an
intermediate. In this chapter we discuss MCRs that meet the strictest definition and
 
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