Multicomponent reactions (MCRs) are one-pot reactions employing more than two starting materials, e.g. 3, 4, … 7, where most of the atoms of the starting materials are incorporated in the final product.1 Several descriptive tags are regularly attached to MCRs (Fig. 1): they are atom economic, e.g. the majority if not all of the atoms of the starting materials are incorporated in the product; they are efficient, e.g. they efficiently yield the product since the product is formed in one-step instead of multiple sequential steps; they are convergent, e.g. several starting materials combine in one reaction to form the product; they exhibit a very high bond-forming-index (BFI), e.g. several non-hydrogen atom bonds are formed in one synthetic transformation.2 Therefore MCRs are often a useful alternative to sequential multistep synthesis.






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Figure 1


Above: multistep syntheses can be divergent (sequential) or convergent; below: in analogy MCR reactions are convergent and one or two component reactions are divergent or less convergent.

Chemistry and Biology Of Multicomponent Reactions

Developments in azo disperse dyes derived from heterocyclic diazo components

2-aminothiophenes by the gewald reaction

Elemental sulfur has been known since Antiquity and found widespread applications in the preparation of black gunpowder, the synthesis of sulfuric acid as well as other sulfur-containing compounds, and the vulcanization of rubber. Over the last several years, we have come to better understand its properties and discover more applications of elemental sulfur in synthetic organic chemistry. This review summarizes the advances from 2000 in the construction of organic molecules using elemental sulfur via sulfuration, oxidation, reduction and redox condensation processes.

Recent Advances in Organic Reactions Involving Elemental Sulfur

Nanomolar Affinity Small Molecule Correctors of Defective ΔF508-CFTR Chloride Channel Gating

Aliphatische Ketone, Aldehyde sowie β-Dicarbonylverbindungen reagieren mit methylenaktiven Nitrilen und Schwefel in Gegenwart von Aminen bei Raumtemperatur zu 2-Aminothiophenen. — Eine Variante der Synthese, die Einwirkung von Schwefel auf vinyloge methylenaktive Nitrile, gestattet auch die Einbeziehung von Alkylarylketonen in die Reaktion.

Horst Böttcher

Papers

Heterocyclen aus CH-aciden Nitrilen, VIII. 2-Amino-thiophene aus methylenaktiven Nitrilen, Carbonylverbindungen und Schwefel